Amiga.org
Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: demonblaze on July 10, 2005, 10:57:26 PM
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Hi I've recently bought an A600 from a car-boot sale with an A500 and 1084S Monitor. The A500 and monitor works peferctly (was a bargain for £40 considering it also included the 512kb expansion) but on switching on the A600 all I gets is a black screen whilst the leds all light up and seem to 'stick'. No noises or anything really. Any ideas?
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Is it equipped with a hard drive?
Can you hold down left mouse button when booting to go into the Early Boot Menu?
We can provide A600 repairs if you have no luck.
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Check if it has still its rom inside. He could have ripped them off, you never know :)
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Thanks for all the feedback. Tried the A600 again with all the psu's I have (was worth a shot :-P ) but zilch. When I turn it on, the power light comes on and so does caps lock but it makes no attempt to do anything else. No floppy drive clicking or purple disk screen. But I'm gonna try and open her up later when it's safe. In the mean-time any other ideas? Thanks
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Just opened up the case and according to the motherboad I have a revision 1.5 machine. All chips seem to be there and unfried although... a chip marked 4.433619 KDS 2E (it's silver and is near the top left of the motherboard)was a little elevated compared to the rest. Could it be that a solder connection is broken on the left side? I see 2 looking fine on the right? And could this be the trouble?
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demonblaze wrote:
Just opened up the case and according to the motherboad I have a revision 1.5 machine. All chips seem to be there and unfried although... a chip marked 4.433619 KDS 2E (it's silver and is near the top left of the motherboard)was a little elevated compared to the rest. Could it be that a solder connection is broken on the left side? I see 2 looking fine on the right? And could this be the trouble?
Sounds like an oscilator rather than a chip, try exerting a little downward force on the kickstart chip (the only socketed chip on the board), it may not be seated correctly.
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Isn't the black screen reporting a missing CPU?
This is the A1200 warning colour, maybe the 68000 is not sitting
properly in your A600.
Another problem could be the machine's SCART plug isn't in firmly in
the back of the display or something simple like that.
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I'll check the kickstart chip and see what happens as for it being scart, it's definetly not. The power and caps led come on together and there's a single click of the drive but that's it. Dosn't even run through the start test which made me think it could be the kickstart chip. Can anyone tell me where I can get another 2.05 chip? Preferabily one which'll let me install a HD bigger than 40mb (v37.500) and you mentioned about it being socketed... that means if I was to replace it, it would require no soldering, right? Thanks for all the help :-D
*Update* I checked the chip to see if it was sitting right and it seems to be. Maybe the chip is just dead and if possible how could this happen?!?
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What makes you think it's the Kickstart chip?
The custom chips will still notify you of a component failure such as bad ROM by outputting a red screen to your display.
I once had a hilarious problem with my X-Box whereby the screen would only display in black & white in RF/Composite modes. After arranging for Microsoft to collect and re-deliver it 3 times, with them totally baffled (and costing them £60 with Securicor), I found out my TV's battery backup was dead and had forgotten the colour settings.
Obviously I didn't mean to cause Microsoft all this hassle and expense. Hehe
Maybe you should get another cheap A600 and swap ROMs to see, at least then you'll be able to eliminate suspicions and have a machine (with accesories!) for spares/sale.
:-)
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Well for one my tv works with all my consoles and other amigas (not to mention that it does the same with my 1084S monitor) and secondly because the power light comes on and sticks... it should flash first as the operating system goes through various tests. And if it was bad CIA chips then surely it would boot up so far and then give me an error instead of a black screen. As for the x-box well, I've got better taste in consoles than that buddy :-P . Heh anyhoo I'm gonna send my A600 to Amigakit when I've got the cash so as to support someone who still supports the best lines of computers ever built :-D
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Hyperspeed wrote:
Isn't the black screen reporting a missing CPU?
This is the A1200 warning colour, maybe the 68000 is not sitting
properly in your A600.
Nope, there is no error screen for a missing CPU..what would the startup code in the ROM run on to test for it?
But as for why it ain't booting, could be any number of things.
Faulty cpu/kickstart or one of the custom chips.
Something shorting out or a damaged trace of the motherboard,maybe the previous owner jammed something in the PCMCIA port and bent some pins together?
The ROM could be checked by putting it in an A500 or A2000, but as everything else is surface mounted there isn't a lot you can do except grab the A600 schematics and spending an evening with a multimeter checking for blown resistors and ferrite beads,dead capacitors and making sure power is getting to the right places.
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Hi
I had an A600 with very similar problems. Thing is if I left the computer for twenty minutes or so it would fire up and run just fine. I would then switch off and dead in the water. You could try taking the floppy drive off and checking to see if the cable undernieth is fitted properly, these can cause this kind of problem, particularly if the cable has been reconnected the wrong way. Capacitors can cause probs on the A600 and I would guess its either a dead chip or a capacitor. The machine was probably faulty when you got it so no way of really knowing.
Anyway I simply got another motherboard for mine and it works just fine now.
Check out the following three pages from my site which will show you the inner workings of the A600. Not much help, but great fun in the end..
http://www.scuzz.org.uk/amiga/amiga_scuzz93.htm
http://www.scuzz.org.uk/amiga/amiga_scuzz94.htm
http://www.scuzz.org.uk/amiga/amiga_scuzz101.htm
For the whole site check out...
http://www.scuzz.org.uk/amiga/a_amiga_inframe.htm
scuzz
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demonblaze: I bought my X-Box in the blissful knowledge that Microsoft made a significant loss on all consoles sold in order to make the profit on games. I buy the games second hand.
:-D
I only got it for Jet Set Radio Futur but despite it being a lump of a machine it's a very good bit of kit (700Mhz Pentium, GeForce 3, 64MB RAM, 8GB hard disk).
The bizarre thing with the X-Box is only now is a console capable of having an operating system hacked onto it by coders and emulators etc. put on it. Even though people were doing much more with the CD32 SX1/SX32 nearly a decade earlier!
As for the A600 problem, yeah it would make sense there's no CPU-missing screen. The thread I read before must have had their wires crossed.
:-D
Wizard Developments (aka Compute!) had a dedicated setup to check for faults and I think there are machines or software that can immediately pick up on some lost signal or timing problem. Maybe AmigaKit.com has diagnostic software to avoid you spending the evening with the multimeter!
:-)
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Heh I hope Bill Gates gets the pineapple when he's in hell (Little Nicky quote there if you didn't know ;-) ) But yup I'm gonna try and raise the funds to send it to amiga kit. I could always buy another motherboard and fit myself but I'd like to support the community. Thanks for all the help though. Now all I need is a set of some workbench 3.1 (Escom) disks to reformat it's hard drive as mine dissapeared when I moved house lol. If it's not one sodding thing it's another... at least my cd32, a500 and monitor is working perfect!
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demonblaze wrote:
Just opened up the case and according to the motherboad I have a revision 1.5 machine. All chips seem to be there and unfried although... a chip marked 4.433619 KDS 2E (it's silver and is near the top left of the motherboard)was a little elevated compared to the rest. Could it be that a solder connection is broken on the left side? I see 2 looking fine on the right? And could this be the trouble?
That oscillator only has two legs and is bent to save space, so it is normal that it feels a bit loose.
When I turn it on, the power light comes on and so does caps lock..
Does it blink or just stay on forever? If it stays on, it could indicate a problem with the keyboard.
Why not try using that ROM from your A500?
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Hyperspeed wrote:
I only got it for Jet Set Radio Futur but despite it being a lump of a machine it's a very good bit of kit (700Mhz Pentium, GeForce 3, 64MB RAM, 8GB hard disk).
Got Jet Set Radio on the DC..
Btw. those specs say nothing. For instance, my DC is equipped with only 16MB RAM.
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Have you tried dismantling the entire machine - remove the keyboard, mouse, floppy, any HDs, etc. Does the machine have a chipRAM expansion board? Remove it too.
See if that boots up.
Then try taking the KS out, and see if that will boot up with a coloured error screen.
Take the whole motherboard out of the metal shielding and check whether there's any damage to the traces on the underside (this may be a bit tedious, as you've got to unfasten all of the hexnuts at the back...)
Apply pressure to each of the main chips - I know that they're surface mounted, but there may be a bad connection.
Leave it switched on without doing anything for about 30-60 minutes. See if any of the components get warm - or hot (I don't think that there's anything in the standard A600 that gets hot to touch; that may indicate a problem).
Can't think of anything else...
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So it's not just me that has this problem with A600s then!
I have a 600 with this very problem - power light on, Caps Lock light on and stays on. Leave the machine on for about an hour and eventually it comes up just fine. I had a solution - another motherboard.... but the new motherboard had exactly the same problem! Different PSU and everything!
I suspect it's the +5V line checking circuit that's not happy but I'm not sure of that - it waits for a steady +5V with not too much ripple, then tells the rest of the machine to boot up, but it seems reluctant to do this!
If I ever find anything else out I'll let you know... could you do the same? :)
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I once had a problem when I installed my Blizzard 1230-IV and a scandoubler and it needed extra juice. It toasted my A1200 power supply and then blew an even more powerful A500 PSU.
Could there be a problem in the power brick as opposed to the motherboard? I know there's a 1-Amp fuse in there that's very sensitive but components could be at fault in there if the A600 isn't getting +5v or whatever.
Maybe you could try a converted 200W supply (or Wizard PowerBox/Goliath).
:-)
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Does this mean that even by buying a new motherboard that I could still be stuck with the same problem? That sucks. The reason I want it repaired is so that I can network it to my A1200/CD32. Sorry about the delayed reply but I've been working ALOT and have barely been online for more than 2 minutes for over a fornight.
Btw I know this isn't relevant but it's just come to my attention that an independent publisher in england is having problems with cash-flow. Why should we be worried I hear you ask? Simple, because it's Live Publishing; the publishers of Retro Gamer, the best and ONLY regular retro magazine. I don't know if any of you have read it but if not then you're missing out. If any of you are fans then please take out a subscription to ensure that this great mag and it's writers continue to have a great future! :-D
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We should have a tutorial on how to repair Amigas now that many of them are two decades old.
Did you get around to contacting AmigaKit.com as they repair Amigas...
As for Retrogamer, I picked it up in WHSmith but wasn't too enthused. I think my main interest started with the Master System although I did love my Sinclair ZX Spectrum +2 128k and I was intrigued by the C=64 and it's cartridge capability.
Retrogamer looked a very confused publication, they should have sections for each decade so that the really basic machines don't bore the life out of the late 80's gamers.
:-)
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Speelgoedmannetje,
What a nickname! (does it mean anything?)
Anyhow, Dreamcasts do NOT have just 16MB of RAM. They have 16MB of main RAM, 8MB of video RAM and 2MB for sound. The DC motherboard is exactly the same as the original NAOMI arcade board, but with 10MB less RAM.
Regards,
Lonewolf10
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No, the Dreamcast has a TOTAL of 16MB of memory.
Sega Dreamcast - 16MB
Sony Playstation 2 - 24MB
Nintendo Gamecube - 40MB
Microsoft X-Box - 64MB
Odd then that a CD32 with SX32-Pro can have up to 130MB of memory.
:-D :-D :-D
The Dreamcast definately didn't appear as technically inferior to the PS2 however. In situations where multi platform games were compared the Dreamcast often had smoother, more refined graphics (Ready 2 Rumble 2). Certainly, comparing the awesome Shenmue 2 on Dreamcast to Shenmue 2 on X-Box will prove that there isn't a significant difference in hardware and the Dreamcast's demise was down to the fact Sega (unlike Microsoft) could not afford to lose $300m a year `buying' the public. Something the Monopolies and Mergers Commission should have been told about. Sony and Microsoft, unlike Sega and Nintendo don't make a penny on their consoles and rely solely on software license revenues. They also report the success of each game division on how many millions of dollars less they lost this year to last.
Dreamcast had the advantage of a visual memory card, something Sony tried to copy with the Pocketstation for the PSone. There's a lot of underground programming going on for the Dreamcast with ports of NetBSD, Linux and emulators for all the old consoles/handhelds. It's become a bit of a rebel machine like the Amiga!
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Well I took it apart, de-dusted and made sure that every chip/socket/plug etc. was pushed down firmly.
It has now worked every time - well I've turned it off and on about 20 times,
It could be because the machine has just warmed up or something. I'll let you know if it stays working
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When you say "took apart", did you actually disconnect anything? (hard drive, floppy, cpu/ram expansion etc?)
If so, does it still work when you reconnect them?
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moto
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Well it seems a lot of A600s are exhibiting the same problems. Black screen with power/drive LEDs and keyboard LEDs on. Or leave it on for a while and it spins up. I have two that each did this, one was Dead with lights on, other when left on for about ~10-20 min would work, but no sound. I think these have to be repaired and it's most likey due to leaking caps on board or ruined traces. It is most likely NOT a bad Kickstart ROM or custom chip. I had these two faulty A600's the past years sitting in a box and decided to do something about them when I saw how much they have been selling for on ebay US. I sent them off to Amiga Center for repairs and they now both work fine.
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Well I took everything apart that looked easy to put back together again :-D I don't have alot of experience with amiga's so I was rather cautious.
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I too have had my A600 not boot up with caps light on solid. Took it apart last night and tried everything in this thread. Got it finally to boot by wiggling (technical term) the keyboard cable at the connection on the motherboard.