Strange crashes..

[rvo_nl]

Hey all, please advise. I'm having troubles with my a1200 lately. Problems started a few months ago, with random crashes while playing 3D games that use the PPC processor. Amazingly, half a year ago I could play games like Quake and H2 for hours without a single crash. (not that I did, since Q1 is rather boring and H2 runs like sh*t, but nice stresstests, no?
 
Naturally, I started to look first for a software problem since this is rather common on a 1200/ppc setup. I've tried every possible combination of WarpOS , Warp3D and CyberGraphX. I've turned off all patches I was running. I left stuff out of WBstartup. I put an old backup back. I did a lot of stresstesting, but it has something to do with the PPC processor, that I am sure of. I havent had any crashes while playing MP3's using AmigaAmp, but in that case PPC is only utilised 30% or something.
 
I suspected a cooling problem, too, so I added heatsinks on all 'hot' chips on ppc+bvision. I even tried putting a desktop fan next to the opened tower, but still the machine crashed albeit not as often.
 
I've checked IDE-Fix, Indivision and ROM connection the motherboard. I've tried running OS4 (I have a triple boot setup) instead, but it doesnt load at all. Ofcourse Ive tried various ENV settings for all related stuff. I did a memtest and swapped simms around.
 
Last, I started looking for a power issue. I still have the original a1200 powertower/elbox PSU, which is rated at 250W. Last year I totally cleaned it out with compressed air and added a new fan. So, I tried disconnecting both optical drives, but still stuff crashed.
 
Then, half an hour ago, something interesting happened. I was going to give Heretic II a try (I wanted to test cd audio output). First I did a timedemo of Quake to see if my system was stable enough. Then I inserted the H2 cd-rom (Keep in mind I normally dont have cd or dvd in my drives) and started the game. Immediate WarpOS crash! I rebooted.. Upon booting, the cdrom drive is spinning up to check the cd in the drive. At the same time Workbench is loading my Workbench backdrop using PPC datatypes. And every time it did this, it crashed straight away, sometimes even losing the blizkicked OS3.9 rom in the process!
 
After some time, I took out the cdrom, so there was no spinning of the drive during boot, and much to my surprise, workbench loaded fine. I was able to repeat this without problems a few times. (I'm pretty sure my machine will still crash with my drives detached though)
 
So, for the few brave enough to have read this far, what do you think is going on here?
 
Software issue?
IDE-Fix Express conflict?
Power Supply Fail?
Dying PPC/Bvision?
 
Would be great to have some pointers before I invest in a new PSU.

[rvo_nl]

yeah I have 2 128MB simms and have tried em seperately in either of the 2 slots. So that is ruled out..

[rvo_nl]

Nothing at all. I've kept track of almost every change I've done to my Amiga, software-wise and was thus able to turn back all changes until the point where it ran stable earlier.
 
And I haven't touched the hardware. At one time I was able to fix the crashes for a day or so, by reseating the ppc card. But this is not 100% confirmed and I havent been able to reproduce.

[rvo_nl]

yeah I'll see what I can do. Perhaps I can find some old PSU somewhere to try out and see if it helps.
 
I did apply fresh thermal paste to the ppc cpu. Will get some contact spray aswell.

[rvo_nl]

thanks for the warning. I was aware of that, but I thought the PSU in the Elbox tower was a pretty standard afair. The tower itself comes with a AT power lead -> Amiga power lead converter thingie. There was something regarding the power switch that looked quite hard though.. Cant remember what it was.

[rvo_nl]

hey all, I  havent touched my Amiga since but tonight I gave it another try. All's fine until both CD-rom drives spin up, then I get that instant crash again. Surely must be a power issue. I dont mind investing in a new PSU. In worst case I have one for spare.

But uhm.. does anyone know how to replace a Power Tower / Elbox PSU but keeping the power switch up front intact? Will any AT PSU do? What about the floppy power connector, that's not standard is it?

[rvo_nl]

thanks for your replies. I was aware of that ianstedman website, but I recall something specific for the PSU in my elbox power tower. I even remember a thread on a site like this about it, but cant find it. will take the PSU out and have a look at the wiring.

[rvo_nl]

The simple reason for it most likely being a PSU problem is I use very much the same set up and the answer to it indeed turned out to be the PSU...

Thanks Franko, I'm so much more confident my PSU is getting old. Will get a replacement ASAP.

@wawrzon, thanks for your concern, but Im afraid I ruled out temperature-related issues. Its freezing over in Amsterdam and this problem occurs when booting from cold, starting OS3.9 and opening both CD-rom trays. And its reproducable. Sure, it could be something to do with my IDE-Fix or even a driver, but when I unplug both drives and demand a lot from just the PPC or Bvision I get crashes, too. So both cd-rom driver and ppc/warp3d driver? I dont think so..

In case you are right (we will know soon enough) I will apologise and will have a nice spare PSU

Still dont know how to hook up the PSU to the Elbox power switch though.. Must find out more about that.

[rvo_nl]

tbh, I didnt even know you could replace that.. It is somehow related to the power issue though, at one time, when I had the 'strange crashes' again, I took the ppc card out and in again. After that, the problem seemed solved for weeks. Could be coincidence.

[rvo_nl]

well, here I am again with a small update. Ive installed a new ATX power supply and got this ATX-AT adapter from Amigakit that sadly is currently connected to the reset button. This might change in the future. More importantly are the results. Im happy to say that I have not experienced any instability issues. All demanding apps run fine, the power led shines brighter than ever before, I can open the cd drives as often as I like, thats all good.
 
There is bad news, too. Every custom screen I open is a bit garbled. Random stripes and garbage. Not a lot, but still, its not supposed to happen. The Workbench is fine, as is every app that opens on the Workbench screen. Its just stuff like IBrowse, Diropus and Quake (1) that have artifacts. To me it seems this can only be a software-issue and I guess I should do a reinstall. But perhaps Im wrong and this is somehow related to the Bvision?

Also Ive noticed OS4 wont start anymore, it quickly flashes blue when loading the ROM and then nothing happens. This could too be the result of the testing I did when my old PSU was giving up, so I dont know for sure whats causing this.

Any ideas are welcome. But please dont tell me I still have hardware issues.. ?