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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: mvansickle on April 14, 2007, 09:48:04 PM
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I have a beloved 3000T that has soldiered on through a lot of hardships (relocations) but this last house move finally did it in. After unpacking it and setting it up, it refuses to display a video signal or (from what I can tell) boot at all. It powers up, fan is on, and the hard drive spins up but then - nothing. I've tried attaching a 1084 and VGA monitor, neither give a signal although booting the Amiga DOES bring the VGA display out of powersave mode so there is some kind of signal there. I have tried reseating ZIP ram (that was fun) and also booting without the hard drive attached.
There really is nothing broken that I can see, the MB is in mint condition, the only thing is that the SCSI terminator on the back of the machine is a bit bent. Could that cause this kind of problem?
Any ideas what else I can look at before I try to find a place to repair it? Gotta have this baby working again! I miss it!
Matt
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Just to be sure- Is the key switched to the ON position? Without the key the machine won't boot.
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Yes, the key is in it and I've tried it in both positions. I wonder if perhaps the wiring has come loose for that piece. Is there a way to disable the key lock?
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No; in that case you should short the two wires.
Have you had a look inside the machine? Maybe you are running an accelerator board which has come loose during transit?
Or; worse; it could be the dreaded leaking battery. They usually do lots of damage...
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mvansickle wrote:
I have a beloved 3000T that has soldiered on through a lot of hardships (relocations) but this last house move finally did it in. After unpacking it and setting it up, it refuses to display a video signal or (from what I can tell) boot at all. It powers up, fan is on, and the hard drive spins up but then - nothing. I've tried attaching a 1084 and VGA monitor, neither give a signal although booting the Amiga DOES bring the VGA display out of powersave mode so there is some kind of signal there. I have tried reseating ZIP ram (that was fun) and also booting without the hard drive attached.
There really is nothing broken that I can see, the MB is in mint condition, the only thing is that the SCSI terminator on the back of the machine is a bit bent. Could that cause this kind of problem?
Any ideas what else I can look at before I try to find a place to repair it? Gotta have this baby working again! I miss it!
Matt
Where are you located, I may be of some assistance. If you are not close to me, check all wiring connections, and if necessary remove harddrive cable and try booting off floppy. Also check to be sure all socketed chips and crystals are secure. If that doesn't work, you might need someone to diagnose it for you which is hard to do online. One last thing is to try to hold the two mouse buttons down and see if you get the early startup menu. Most important, don't give up, 3000t's are terrific. :-)
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Tahoe wrote:
No; in that case you should short the two wires.
Have you had a look inside the machine? Maybe you are running an accelerator board which has come loose during transit?
Or; worse; it could be the dreaded leaking battery. They usually do lots of damage...
Hey I like your site! I hope you finish it, manuals etc.
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I am in Castle Rock, Colorado. I am terrible with electronics (at least at the level of checking wiring, etc) so I'm at a loss what to do next. It may be something as simple as this keylock not functioning anymore, I can't remember if you are supposed to see a video image when it is in the locked position. What I am seeing is the monitor turns on from powersave mode but I get no picture.
It has been so long since I had to do any troubleshooting on an Amiga I'm really lost. If I boot the machine without the hard drive connected I am assuming I should see SOMETHING prompting me to insert a disk or something but maybe not. I haven't actually tried booting it with a kickstart disk in the floppy drive.
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If you disconect the SCSI cable from the controller, you'll have the screen asking for a floppy on boot.
If the terminator behind the case is bented, they could be broke. Put it out and send to any electronics near you to check, the SCSI chain could not run without proper termination.
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What would it do if the termination wasn't working? Would it just not boot at all or would it show up on screen asking for a floppy?
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Also another update - I know the drive is not dead because I bought an Amiga 2000HD from a local guy today and plugged my A3000T drive into it, it worked just fine and booted up to my old system. Awesome! I don't like how slow it is compared to my 3000T though. ;)
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It might show the symptoms that you describe (IE no Video)
I remember SCSI/Termination issues with my A3000T many years ago. Thing is, the A3000T can take FOREVER to go to the default "Kickstart Floppy" video screen when the SCSI isn't correct. You may not be waiting long enough to see it. Pull the SCSI cable from the motherboard and give it a good 5 or 10 minutes before you decide there isn't any video.
Another time I was using the A3000 Batmem utility for something once and changed a SCSI bit. It took SO LONG to boot up after that I thought I killed the machine but it eventually came back up.
I think the power light should go Bright-Dim-Bright when the machine first powers up, is yours doing that? Also check and see if you can access the early startup screen by holding down both mouse buttons at power up.
Keep us posted and don't give up on it.
Jeff
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I thought that you could repeatedly press a key (Caps lock?) and if after a while it never stops blinking then the 680x0 isnt working?
Not sure the exact details but worth looking into.
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The power light stays on continuously, it never flashes.
Holding both mouse buttons during boot didn't do anything.
I actually left it powered on for a couple of hours once (before I took the drive out) and it never booted. I have it on now with the SCSI cable disconnected and will leave it on for a few hours to see if anything changes.
One thing I noticed the last time it worked was that the hard drive seemed to be going bad - i.e. sometimes it would not boot properly or would freeze when loading the system. I have not been able to repro that since I put the drive in the A2000 so now I'm thinking it's something to do with the SCSI controller that was going bad.
Anyone know if there's a way to disable the onboard SCSI controller? If so I could put the SCSI card + hard drive from the A2000 into it and see if it boots.
I guess first I need to get it to boot to the kickstart screen before I start worrying about getting the drive working in it though!
I have a feeling that finding a replacement motherboard for this guy is going to be damn near impossible. :(
Can anyone give me step by step instructions for bypassing the keylock, just in case that turns out to be the problem?
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alexh wrote:
I thought that you could repeatedly press a key (Caps lock?) and if after a while it never stops blinking then the 680x0 isnt working?
Not sure the exact details but worth looking into.
I tried this and indeed, after pressing Caps Lock a few times it stops blinking.
Anyone know exactly what this means? Fried CPU?
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Or fried Agnus.
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Since I had retrieved my data by moving the drive over to the A2000 I got brave and took apart the A3000T tonight.
Sadly, I seem to be a victim of the leaking battery. I can see where a drop of acid has fallen from the battery on to the motherboard and disintegrated 2 or 3 traces. Argh!!! I wish I had known about the battery problem sooner. :(
I don't suppose there is any way to repair this?
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There is a way of cleaning this up (can't remember what to use but someone on here has done it) and then you can re-draw the traces with a trace-pen (sorry I don't know the technical name for it!)
I'm sure someone will fill you in better - for now at least, don't give up!
:-)
Matt
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You know, I just realized my wife's brother here in town builds his own electronic devices (pcb from scratch, etc) as a business and could probably repair the traces on the board in his sleep! *slaps forehead*
What is involved in removing the battery so he can do the repair? Do I just need to cut the metal clips holding it to the motherboard?
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Preferably, dessolding the leads are better than simply cut it.
If you don't want another issue like that, buy a lithium battery pack instead (could be even a cell phone 3.3V one), or other simply modification like this (some people put a coin shapped peecee battery plus a germanium diode to avoid recharging - this type of battery couldn't be recharded).
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Well the board got worked on for almost 2 hours without success so far. The vias around the math coprocessor were all damaged but the traces everywhere look OK. We tried putting wire in the vias and soldering on both sides but no luck so far. There is damage underneath the ROM vias as well so that's next, but we're done for today. I'll keep everyone posted, and hopefully there will be a happy ending to this saga.
Thanks everyone for your help so far!
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For more info you can look below, although you're doing the right things with the vias, and sadly it's not working :(
My favorite New Zelander, Castellan has lots of good stuff here:
http://amiga.serveftp.net/hardware_repair.html
This one too
http://members.iinet.net.au/~davem2/overclock/batt.html
And pertinent forum posts:
http://www.amiga.org/forums/showthread.php?t=26702
http://www.amiga.org/forums/showthread.php?t=21940
http://www.amiga.org/forums/showthread.php?t=20331
http://www.amiga.org/forums/showthread.php?t=13844
http://www.amiga.org/forums/showthread.php?t=22702
http://www.amiga.org/forums/showthread.php?t=23271
Lastly: my A3000 is still dead, because of a battery leak, so it's not something easily escapable. I wish you lots of luck, because that's what's needed in this case!
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Don't forget to connect the keylock when you do testing !!
(talking from experience here, took a while to find the machine actually worked; but I hadn't connected that darn key; which meant black screen and no sign of life)
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Anybody know a place that still services these? If we can't get it to work, I'm going to want to ship the motherboard out to an expert. Recommendations? Thanks in advance!
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Hi, did you ever figure out what was wrong with your 3000T? I just started having problems with mine today and it is the exact same symptoms. I have a Picasso IV and Cyberstorm PPC board in mine. I have disconnected everything from the motherboard except for floppy and still get the black screen Shows a video signal but no picture, just black. Tried my Picasso IV and Cyberstorm in a desktop 4000 I own and they work both work fine so I know it has nothing to do with them. Have nothing on the SCSI and the terminator is on the back of the machine. I removed my battery long ago so I know that has nothing to do with it.
I screwed up the boot track on my UW SCSI drive and was trying to get back up and going by booting with 3.1 floppys (all I have and a scsi drive). Was trying to get 3.1 to recognize my SCSI CDROM so I could get to my 3.5 install CD and reinstall 3.5. All of a sudden my machine quit showing the insert disc screen and has been black ever since.
Anyone that could help with suggestions, I sure would appreciate it.
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@tlgrooms
well have you checked the battery?
fixing the corroded traces is easy, the problem is finding them.
cheapest but ugliest solution is to just soldier wires. or use liquid silver and such.
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Orange,
Not the battery on mine, I removed it a long time ago before any trouble began.
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oh, sorry, didnt read the first message completely. still, its worth checking the area once more, to be sure. (if it ever had batt leakage).
i think you would need two terminators if it has external scsi. check that too, or put some drive on scsi. without proper term, it probably wont boot.
have you checked all video outputs?
what about LEDs on power up, does it pass the initial test?
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Orange,
Machine was booting fine from floppy until last night. I hooked up an older SCSI CD-ROM drive that I used to use on the machine to the built in SCSI on the 3000T motherboard. Booted several times from floppy and was never able to make hdtoolbox see the CD-ROM drive. Tried changing termination, scsi id's etc and somewhere along the way the machine quit booting. So, I pulled all the cards and took the scsi cable off the motherboard and still nothing. Removed the Cyberstorm as well and went all the way to nothing but the built in video connector, same thing. When I power on, a video signal is detected but the screen stays black and the floppy never starts clicking like its trying to boot, no boot screen. So, with nothing but the bare motherboard and the floppy hooked up and video plugged to the motherboard, nothing but a black screen. SCSI on back of machine is terminated with the terminator that comes with the machine. SCSI Cable inside is completely disconnected from board. My ethernet, picasso iv, cyberstorm cards are all OK thank goodness as I've put them in my 4000 desktop and they work fine there. Man I wish I had created an emergency boot floppy and made several backups. This has been a nightmare and I still can't get the machine to boot. I own many Amigas but my 3000T has always been my favorite. Bought it new shortly after they came out.
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Think K.I.S.S.. start with the power supply, check the voltages on the +5 and +12 on a drive connector with the machine powered. if they look low on either one could be something to do with the trouble.Check the clock battery,usually cylindrical and near the top of the board inside,has it leaked? look for greenish corrosion on it and nearby components. I'm guessing its time to pop the chips and reseat them,don't bother just pushing on them as some people say,this is almost never a reliable fix, its best to pull them and reseat.I am assuming this does not have a 040 card,but if it does it may need reseated. Chip ram can cause this,some of the socketed chip ram can be making bad contact,again reseat them if you can.
Need some more info.. can you hear the hard drive spin up? any flickering or color change on the screen? is the Flicker fixer switch on 31khz on the back if your using a regular pc vga monitor? is it off if your using a 1084 or some such?
good luck,
mIke
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well, I think the problem is with disconnected scsi cable.
I never owned A3000T, but (IIRC) in all other scsi Amigas, if I disconnect everything from scsi controller, it wont boot because its not terminated. try once more with HDD (jumpered with term on) connected to that scsi.
also, when powering up, does power LED change brightness?
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Contact Anthony Hoffman.. I have his email address. Just post me private.
He is the guy I will be sending my boards to. I'm sure he won`t mind me giving out his mail address
PS Do not try to remove the battery. There is a railway station full of tracks below this baby and seriously you could destroy the motherboard.
http://www.commodore-amiga-retro.com/amiga/amiga_scuzz69.htm
PPS I have moved on long journeys an A4000T and A3000T and surprise surprise neither worked when I hooked them back up. Quite a common problem. I wouldn`t mess too much cus it really will be just a loose board or connection. Your best bet is to preserve the computer first and get someone skilled to remove the battery. They can check for electrical continuity. It will NOT be anything serious. What is serious is the preserving of this machine. Its at times like these you can do real damage. Slow down, pause, don`t panic and take things one step at a time. The battery must be desoldered by someone who knows what he is doing. After that its just maintenance.
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Hooked up scsi drive terminated to internal scsi connection and still nothing. Power LED never changes brightness once it comes on.
Scuzzb494, removed battery 10 years ago. Never replaced it and never had a problem after removing it until now so I don't believe that has anything to do with it.
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um, did you check that keylock thing mentioned here?
otherwise, you should try the 'usual procedure'- press on every socketed chip, check PSU contacts, RAM modules.. if possible see which chips get (too) warm.
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Contact Anthony Hoffman..
I've been speaking with Anthony over the last few days, it looks like he's only got a week or two left before he heads out to the bottom of the world and he won't be back till November 2011.
So I think your A3000T MB might have to wait a bit... I'm going to check my A3000T tonight after all this discussion...
It's been sitting behind me in the cpu room for about 2 years since I got it up and running (brought it dead) and I don't think I removed its battery...
:)
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Hooked up scsi drive terminated to internal scsi connection and still nothing. Power LED never changes brightness once it comes on.
Scuzzb494, removed battery 10 years ago. Never replaced it and never had a problem after removing it until now so I don't believe that has anything to do with it.
I thought this was a thread by a guy called mvansickle who said he had a leaky battery. have we flipped into different threads here...
He said....
Sadly, I seem to be a victim of the leaking battery. I can see where a drop of acid has fallen from the battery on to the motherboard and disintegrated 2 or 3 traces. Argh!!! I wish I had known about the battery problem sooner.
I don't suppose there is any way to repair this?
I was replying to him. I have no idea what your problem is. Confused.
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I thought this was a thread by a guy called mvansickle...I have no idea what your problem is. Confused.
You stepped into a Soap Opera of sorts that revolve around Amiga Hardware namely the Amiga 3000T. You see one Amiga 3000T appears to be dead but its twin brother showed up claiming its the father of an Amiga 4000 that the original one had with a v-e-r-y loose Amiga 1000.
Now, one Amiga 3000T is naked and is about to come out of the closet to see if its 'battery' is damaged. Also, I believe some Amiga Doctor is going 'south' until 2011.
I'm really quite hooked because I've been following this for over 25 years so I want to see how it comes out...
To bring you up to speed:
1 dead or dying Amiga 3000T that was fine until it moved to a new 'town'. Its brother (an Amiga 2000) was able to rummage through its stuff and boot. Could the Amiga 2000 have had something to do with the 3000T's sudden coma?
Another Amiga 3000T has also suddenly become ill as well. Nobody is a suspect right now...though a battery was accused but found to be gone.
However, one battery has been identified in I believe the first one Amiga's illness. The battery has been 'taken care of' but many traces were lost in the ordeal...
So what is causing one of the Amiga 3000T's not to boot? So many guesses: bad keylock, the usual suspects (Gary, Buster, Amber, Paula, Denise, the CIA, Agnus, etc..), a curse of some sort??
Will all the Amiga's make it? Who will bring them back from the brink? Where is the Amiga Doctor going? Is the closeted Amiga still ok?
You see, its much more than a thread....
Cheers!
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Going to try pulling and reseating the chips. I have a working 3000 desktop also I can swap some chips with. Can anyone point me in the direction of a good tool to pull the square chips with?
The guy who started this thread hasn't posted here in 3 years. I originally asked if he got his machine working because mine was showing the exact same signs as his with the video signal but blank black screen and power led never doing anything but coming on and staying solid.
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heh Pentad, too funny.
tlgrooms ~ get a PLCC extractor for the deep socketed chips or else risk damage to sockets if attempting to remove with a screwdriver. Same with the DIP chips, use a DIP extractor.
My A3000T has similar issues. Although it's been a while since I've attempted to resurrect the unit. Missplaced the notes I've made of it's startup symptoms. I keep forgetting about the lock key hotwiring... Now I want to skip work and tinker with the beast.
If I also recall, Anthony Hoffman did some work on an A4000D for me several years ago. Exellent resource.
We should get a count of how many nonworking A3000Towers are out there...
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Swapped all the socketed chips in my 3000T with the ones in my 3000 desktop (known working) except for the memory chips without any change. sigh....
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Swapped all the socketed chips in my 3000T with the ones in my 3000 desktop (known working) except for the memory chips without any change. sigh....
Just curious and admiring your efforts to get the machine going...
Isn't it a real possibility that your power supply has failed? If it is not able to provide enough 'juice' anymore due to age you will have some weird effects. As LED's and things will probably only draw a little current on 5V they might still work.
Jus a guess, maybe you can get a cheap ATX to Amiga PSU adapter cable somewhere to test this...
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@tlgrooms
well have you checked the battery?
fixing the corroded traces is easy, the problem is finding them.
cheapest but ugliest solution is to just soldier wires. or use liquid silver and such.
That works... I had fixed a 500Plus which had a damaged trace (due to leaky battery) and soldering a wire to act as a bridge worked perfectly.
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Way back my A3000 died in a very simular way. I spent like $300 (ripped off) to have it repaird and it died again a month later. I left it for dead. Five years later I revisited it only to find the problem to be the daughter card wasn't seated perfectly.
If it's not seated perfectly or the connetions are a little dirty then it won't boot.
I'm not sure if the A3000T has this problem or not though...
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the problem to be the daughter card wasn't seated perfectly.
I'm not sure if the A3000T has this problem or not though...
The A3000 Tower does not have a daughter card.
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More bad news, just checked my power supply and it appears to be working fine. Keylock appears to be fine as well.
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Remove the Cyberstorm. Change the jumpers on the MB and see what happens.
Jumper setting
060
100 3-4
102 1-2
104 1-2
103 2-3
040
100 3-4
102 2-3
104 2-3
103 1-2
030
100 1-2
102 2-3
104 1-2
103 2-3
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Don27Dog, tried removing cyberstorm and changing jumpers, still no change.
I tried my cyberstorm and picasso iv cards in my 4000 desktop and they work fine there.
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Did you ever get this working? I had similar issues with my A3000T. Turned out to be the CSMKII card and its on board oscillator. I had to reseat the card and also make sure the oscillator was seated in firmly by bending the pins. It was apparently not getting a good connection. It now works great.
A little tip. When you first power on the A3000T the green LED will start to blink immediately. If it does not blink, something is wrong and it will not boot. (CPU problem?)
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Never did get it going. Going to drag it out again one day soon and start troubleshooting all over again. If I remember correctly, when I turn it on my monitor goes to a black screen (video signal present) and the green LED comes on and stays on solid.
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Well I'm back again and after almost 5 years trying to get my 3000T going again. Can anyone tell me what happens if the keylock is bad? Would this cause the machine to come on to a black screen with a solid power light? That's what mine does, hard drive light flickers ever so lightly (with no drives hooked up) and power light comes on and stays on solid. Do I just wire the 2 wires together to bypass the keylock?
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Well the moment you plug VGA cable into the monitor it gets ground signal and "knows" something is attached but that doesn't mean any part of that something is sending picture so that won't help diagnosing.
Since your floppy isn't clicking I "suspect" PSU , you can measure voltages with any multimer , just set it to 20 V setting and not on high voltage :)
Even better if you have spare PSU to try you might try that and before you do make sure that it's in "vanilla" state (same as it came from commodore).
Apart from that something might not be seated right.
P.S. Keylock behaviour was explained in this thread I think.
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Another thing to watch out for is that the A3000 has to have the daughter board plugged in before it will boot up. Now the A4000 will boot up without the motherboard. Good Luck on your endeavor, I have been working on my A3000 for the last 5 years, bought another one 4 years ago and it quit working this year. (big sigh), but at least my old A4000 still works but it is starting to start up with a yellow screen (oh no). My other A4000 worked about 5 minutes after I bought it, back in 95, but the good news is my old A500 is now fixed and working it was the Gary Chip gone bad. Now another piece of good news is that my CD32 still works, now only if I can find my SX-1. See what moving does to you. Still trying to sort out my disk collection of IBM and Amiga disks, the moving company packed them up all in one box, yes they just dumped them in, I guess the disk god wanted to have some fun with me. Found my new 5.25 disks for my C64 but only the blank ones, have yet to find the program disks, I think they are gone just like my A1000, isn't moving fun. My old A7nX PC computer arrived in 5 different parts as well as my old MSDOS machine, now if I can only locate the case. Got the MSDOS machine (motherboard) video card, floppy drives, memory and cdrom, don't know if the CDROM still works, but the basic stuff still works. Never put your wife in charge of moving while you are working your new job, when she moved my computer room it has been 10 years and I am still sorting stuff out and rebuilding. Good Luck on you A3000 mine used to work, but now what can I say. If the guy in Panama City Florida that grabbed my A1000 still has it can you please return it. It is in a Gray xerox typing machine case, with an Aspirit board, 68010 accelerator, Supra HD Scsi card, 5 hard drives, with seperate power supplies so that I can turn each one on or off, a supra modem, and 3 disk drives. See what happens when you tell your wife that all the computers in the garage can be thrown out, but then you forgot about your build up A1000 and C64, oh yeah forgot about my C128 desk model. But as luck will have it, I still have another 4 big boxes to go through but they will probably be cabling and wire. 10 years and still going through boxes and sorting. You should of seen my Otrana suitcase lugable computer. Can you say pancake. but the keyboard broke away from the case as it was flattened. Never move again, if I do I will sell every computer that works before I leave.
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If the keylock is bad the mouse and the keyboard won't work, the machine boots up fine, found the key to my Amiga 4000 and tried it. It booted up, but no mouse and no keyboard. Forgot about it the next day, and was ready to pull my machine apart when I noticed the key on the shelf where my monitor sits, tried it and got my mouse and keyboard back. Wouldn't know what to do without my A4000. Guess I would have to move everything over to my A1200, which isn't hard to do since it is on a CF card that is used just as a data drive. Good Luck on your Endeavors of fixing an A3000, where is Dave Highnei when you need him, he designed these conglomerations. Six or Seven Amiga models and not one of them can be used like another. One is scsi, one is ide, one is pal, the other is ntsc, one is 23 pin video, the other is vga, even the floppy drives will drive you nuts. Why do I even stay with an Amiga? I must be nuts!!!
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@tlgrooms (http://www.amiga.org/forums/member.php?u=5887)
Any luck ? :P
If not try English Amiga Board hardware forums.
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Thanks for responding. Going to try checking the voltage on the power supply again tonight since I am going to have access to a working multimeter. I'll post here later what I find out. I don't guess anyone makes a power supply converter for ATX to 3000T. I know there is one for the 3000 Desktop. I also have my original 3000 Desktop and it is working so I have been able to swap all the cards and chips out with it and know that they are still working.
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Is there battery damage? look for burned traces. I would guess that is a better guess over the power supply.
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I hate to ask this, is PSU being tested under load?
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Checked the power supply both under a load and with nothing but the motherboard hooked up. It isn't the power supply. There is no battery damage, I removed the battery long ago when storing the machine and never replaced it.
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Did you swap out the PALS with the working 3000 desktop?
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I swapped every socketed chip one at a time that I could except for the zips. None of it made any difference. The 3000 desktop still worked fine after I swapped the chips. I moved them all back as they were originally after I finished checking them. I have not pulled all the zip chips out of the 3000T. I guess that will be my next step.
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Swapped all the socketed chips in my 3000T with the ones in my 3000 desktop (known working) except for the memory chips without any change. sigh....
The 3000T is quite robust and i have worked on quite a few in my time. things i have found that do go wrong:
Power supplies(start here..check it under load. +5v rail should be at least 4.92v or they wont boot in my experience.
12v should be at least 11.92 or the same can result. you're mileage may vary here if its borderline.
check the oscillators are seated well,they are socketed.
Battery damage can be the cause of the black screen and the caps light quits toggling after about 6 tries. Look for broken traces to the rom,cpu,etc in the damaged area.the cpu is not likey to be dead,just a trace somewhere. If you have a A3640 accelerator,you might be able to change jumpers and test with that to get the machine up.
Bad roms: they have failed(bit rot)? or are making bad contact/corrosion from the battery leak. if you see green corrosion,don't try and clean the sockets etc,replace them.
Bad chip ram.. sometimes can cause a black screen. Seems some Toshiba brand zips go bad in the chip ram,i have replaced ram on 5 machines with this problem in the past. change ram as a absolute last resort
Denise socket, i had one intermittent machine with a bad Denise socket,it seems it had a pin broken between the socket and the board that make contact sometimes, you could not see it and it looked perfect.. this was a fun one to find! It was likely a factory defect and gave the original owner hell.
From what you describe,you have a broken trace near the leak. they can be a pain to fix.replace any sockets near the area and check every single one in the area for continuity!
use proper plcc pullers and not screwdrivers..messing up plcc sockets will cause more grief than anything.
sadly the battery has been known to cause problems in amiga since the mid 90's.. its a shame people didnt take them out then!.
good luck.
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If the keylock is bad the mouse and the keyboard won't work, the machine boots up fine, found the key to my Amiga 4000 and tried it. It booted up, but no mouse and no keyboard. Forgot about it the next day, and was ready to pull my machine apart when I noticed the key on the shelf where my monitor sits, tried it and got my mouse and keyboard back. Wouldn't know what to do without my A4000. Guess I would have to move everything over to my A1200, which isn't hard to do since it is on a CF card that is used just as a data drive. Good Luck on your Endeavors of fixing an A3000, where is Dave Highnei when you need him, he designed these conglomerations. Six or Seven Amiga models and not one of them can be used like another. One is scsi, one is ide, one is pal, the other is ntsc, one is 23 pin video, the other is vga, even the floppy drives will drive you nuts. Why do I even stay with an Amiga? I must be nuts!!!
lack of experience? haynie designed the desktop models-2,3,4K(except the 1000). all of the big box(except 1000) can do pal or ntsc with a simple jumper change inside. George Robbins did the 500,600,1200.
All amiga floppies (maybe not the 1000)can be used on any amiga,but may not necessarily fit physically. All amigas have 23pin rgb out. only the 3000 had a flicker fixer for 15pin vga 31khz out.
The 4000 was the only ide big box model. it was a cost reduction. scsi can be added/used on them hence the zorro expansion bus- or better yet, scsi on the accelerator which is usually better.