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.

[x303]

Have you checked your memory cards already ? You might wanna clean the pins.

[rvo_nl]

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

[the_leander]

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?

Ok, my first question would be, what's changed?

You say this behaviour started a few months ago, did you add or remove something a few months ago in terms either of hardware or software?

[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.

[the_leander]

Sounds like it could be time to break out the alcohol to clean up all your connector contacts.

Might also be worth reseating the heatsink on the ppc and applying some fresh thermal paste.

[amigau]

I would still check into the PSU - maybe take it to a PC shop (because they can't complain about amiga stuff if you leave the Amiga home - and have them test it?  Or if you are electrically inclined, do so yourself.

I had an accelerated A1200/68030/50 with the microbiotics card in it and everytime I had weird issues, it was from using the stock PSU (which definitely is NOT up to the task).  moved to the much uglier but more powerful one I got from an amiga dealer, and voila, problems gone.

May not be your issue but definitely worth a wee bit more investigation to rule it out.

amigau
http::/www.amigau.com

[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.

[amigau]

remember that not just 'any' PSU will work - besides the custom connector, it has to be putting out the right voltages/etc.  Which I do not know offhand, save pretty sure that they are a bit different than vanilla PC-PSU output.  I will try to remember to do some digging tonight to see if I can find what they might be, but be forewarned in any event.

amigau
http://www.amigau.com

[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.

[x303]

The tower itself comes with a AT power lead -> Amiga power lead converter thingie.

My psu has this one too, but I also have a standard power connector going directly from the psu to the hd.

[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?

[doctorq]

Any AT PSU would be suitable for replacing the current PSU. It might be difficult to find one though, so ATX with ATX to Amiga adapter might be easier to find.

The floppy power connector is bog standard, so it will be on any PSU you find.

[PanterHZ]

Any AT PSU would be suitable for replacing the current PSU. It might be difficult to find one though, so ATX with ATX to Amiga adapter might be easier to find.

The floppy power connector is bog standard, so it will be on any PSU you find.

Yes it will probably be easier to find an ATX PSU nowadays, and you can use either a ATX to Amiga or ATX to AT adapter, or you can hack the wires & connectors for youself.

I'm not sure what type of power switch your tower has, but if it's the old AT type, you can probably connect the wires from it to the green wire (PSU ON) and one of the black wires (GND) of the ATX PSU connector.

For more info about hacking ATX PSU's for use with Amigas, you can take a look at this page: http://www.ianstedman.co.uk/Amiga/amiga_hacks/Amiga_Power_supplies/body_amiga_power_supplies.html

[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.