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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: Vanfanel on July 26, 2011, 05:34:48 AM
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I'm having all sorts of problems now, aren't I? But I digress. My A1200 and it's accelerator (DKB Cobra 030/33 w/68882 32MB) just don't seem to get along very well. Half the time I turn the computer on I just get a black screen, with the power led flashing (6 short 1 long). Usually, just reseating the RAM is good enough, until it happens again. Lately, the machines has started to reboot on it's own, and tonight, I get a yellow screen when the accelerator is installed. I pulled it out and reinstalled it (as I have done before when I had this problem), only to have it yellow screen on me after it finished booting and had Workbench visible. I'm inclined to think that it's time to take the accelerator out back and put it out of its misery, but logic forces me to admit that some may be wrong with the motherboard as well. Since I'm stuck in Florida, where we have no one who services these things (I know where a guy is that used to, but he doesn't anymore), anything I should check before I start looking into a new accelerator?
And just to keep me from opening another thread, feel free to make accelerator recommendations, too. I mainly game on this, but I wouldn't mind doing more with it in the future. I'd also like to be able to disable the accelerator on bootup, just in case I need too
As always, thanks for your assistance.
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The first idea is obvious, but
could you try the accelerator in another A1200.
Also I am not an A1200 expert (don't own one), but is it possible that the power supply is not large enough, I use to have similar issues in the old Amiga 500s when you attempted to upgrade things like processors without upgrading the power supply
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do you have hard drives or other stuff in your 1200? Power supply can be an issue then.
For recommendations, the ACA 1230's from individual computers is hard to beat these days
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Motormouth, it is an obvious test, but I don't have access to another 1200.
And to both, I've heard about the new ACA 1230's and they sound pretty sweet. I wonder if they can be disabled on boot, though. Or disabled in any way without removing them.
Also, I should note I'm using an A500 power supply at the moment. A bit more power than the anemic 22 watt thing they expected you to use, as I understand it.
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I had this model of accelerator, new, and had the same problems as you and the cause was it would overheat. I put a heat sink on the cpu, and I bought some rubber feet to lift the A1200 and ran it without the trapdoor cover. It helped, but not in 35+ C degrees. In the end I sold it.
If you can get a fan for it it may do the trick.
Acclerator recommendations. The Blizzard cards seem to be reliable and can be disabled with a key stroke.
I ran an Apollo 1240 for years without a prblem though, until it yellow screened, was repaired by PG due to a fried CPU and is now a 1260 running at 40 mhz (not 50 mhz), but never crashes.
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Some of the problems I've been having seem like they could be due to it overheating, but from a cold boot would suggest something more is wrong. In either case, I think it has to go. I know of the Blizzard cards, and they do seem very reliable, plus the SCSI addon is most useful. Finding one for a reasonable price however is tricky at best.
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Just grab an ACA, when's the last time you could buy a new Amiga 1200 accelerator with a warranty?
I really love my 56Mhz ACA, custom OS 3.9 ROM kicked to FASTRAM (no restart required) and a nice fast/stable 1200 :)
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NovaCoder: I can't deny you have a very valid point there. I was holding out for a Blizzard for the SCSI kit, but there are other ways for me to get a CD-ROM on this thing. As for any incompatibilities that might arise from not being able to disable it at all, well, I still have my 1k for that. Can't deny the appeal of "One Amiga to Rule Them All," but maybe that's just not possible.
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I know of the Blizzard cards, and they do seem very reliable, plus the SCSI addon is most useful. Finding one for a reasonable price however is tricky at best.
I had to use tape to fix my scsi board in place. I ended up leaving the case screws off my a1200 as I was having some problems with it. Of course now I've lost them....
I think some of the problems I was having were due to a dodgy ide cable causing the machine to lockup randomly. I guess if I actually used the scsi board for anything other than extra ram then ide wouldn't be a problem.
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Hi Vanfenel. I think your DKB accelerator is acting the same way the three DKB expansions I have used act, and I hope the solution to the problem is just as simple as it was for me, and a few friends who also have these DKB boards.
First thing to do might be the crash test. Turn your Amiga on and let it boot into Workbench. Bash underneath your desk, around the area where the accelerator is, and see if it crashes. Does it crash when you bump the desk with your knee sometimes? A very common problem with DKB A1200 accelerators and RAM cards is the edge connector. The "teeth" inside the connector become loose over time, and don't bite down on the A1200's expansion edge. When the card wobbles or heats up, the position of the pins might temporarily disconnect from the board and cause a crash and reboot.
The solution, if this sounds like it might be the problem, is to take out the accelerator and carefully (using a sewing needle or tiny screwdriver) bend each of the teeth inside the edge connector inwards, on both sides, so that it bites down really hard. If you do it right the accelerator will be a real bitch to push back on, but at least you know it won't crash so often anymore once it's in there since it's much more securely fitted now. Just be very careful when bending the teeth not to bend them in too far!
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Or just use UAE on a 3 year old Netbook.... I'm jus sayin...
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and require another OS and have that os influence the experience, be succeptable to the hosts malware and other problems,etc.,etc.....
....Im just sayin'....
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I hear ya.. but I'll take a malware fix over tryin to fix a 15+ year old CPU card. You're talking to a guy with 2 A1200's who has owned CPU cards from GVP, DKB, Phase5, Apollo, Paravision, and Jens.
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I probably shouldve put some sort of smiley in there. Without the benefit of tone and/or infliction things can sometimes come across differently than intended.
While I do understand why an emulator might appeal to some people, and I concur they do have some advantages (speed being the obvious one if using an x86 machine) they really are different kettles of fish. I personally enjoy my amiga more than I ever liked Winuae, and even amithlon (which I much prefer over winuae and used as my main "amiga" for a number of years) struggles to find deskspace these days. I like the warts and all charm of the real thing.
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Cammy: I will give that a try. I had a theory that a loose connection could be the problem, but I never tested it so... forcefully. Bending the pins a little is simple enough. I'll probably end up replacing it anyway, but at least it won't be an urgent thing.
Crom00: UAE is a great program. I've been following it for years since I first found out about it. But if that satisfied my Amiga fix, I would have never bought the 1200 or took my 1k out of retirement.
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Hello,
I had a dodgy DKB Cobra accellerator card too, the exact same model as yours. What I found was that it would crash frequently but ONLY if the data cache was enabled. It may have been the instruction cache, my memory is foggy, but I think it was one of them.
What you can do is try booting into a Workbench with the command Setpatch disabled....because Setpatch actually turns on all caches (even if you disable caches by booting into Amiga Early Startup Control (the two mouse buttons upon boot).
So definitely see if turning off the caches makes a difference. If so, find out which cache it is. If this is the case in your case, then like me you'll probably want to get rid of the card (drove me nuts). I just assumed the CPU was faulty and I gave the card away. Otherwise you can use:
C:Setpatch NOCACHES (leaves caches alone)
Then use the C:CPU XXXX XXXX command immediately after Setpatch to enable specific caches of your choice. I can't recall the syntax, but just do a CPU ? in a shell window to find out the correct arguments.
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Interesting, Paul. I'll have to check that out.