Any news ?

Sorry for the lack of updates!

I have gone throu the card over and over and cant really see anything that would indicate what the fault is.
A couple of traces on the backside have exposed copper from when someone tried to remove the label I guess. But all traces checks ok with continuity and no resistance.
I tested all passive components for continuity and all seems to check out.
But I found that all the capacitors that are connected to ground behave a bit diffrently then the other ones.
The all read ~330 Ohm when measuring continuity and also when measuring resistance.
All other capacitors reads 0 Ohm on continuity and on resistance it goes up to infinity.

Still I think the problem is the BGA under the main chip or a plane inside the PCB.
I tried to remove the heatsink, I first heated it slightly and tried with a razor but it's really glued on tight!
I didnt have the guts to try any further.

So same issue, boots sometimes, maybe 1/10 but if back corner is slightly bent it boots 10/10.
When it has booted it runs stable.

Anyone got any suggestions what to try next?

The back of the card in the BGA chip area seem's 'well baked' . Have you tried to press the heat sink/bga chip at startup without slightly bending the pcb? If it posts then it could be from the solder balls under the bga chip. 'When it has booted it runs stable.' then the chances of being from a bad memory connection are low (when you release the pcb you should get artifacts or some kind of functional reaction/this is true only if you tested properly the card when it starts and not only check if you can boot to OS and install drivers). The way it reacts sounds more like a startup sequence power/bios/bga connection/bga chip failure.

Have you tried debugging it in dos to see if you can figure out where it fails? I dont much about this stuff but vswitchzero has some intersting videos repairing 3DFX cards but I havent seen any Banshees in the bunch.

I have tried pressing down on each chip, middle and each corner and tried booting this includes main chip with the heatsink without any positive result.

My test is that I tried gaming with the card, mainly Blood and Unreal, for about 30mins. I have tried longer periods aswell.

Thats for the debuggning tip, havent tried that.
I think I got some pci GPUs left somewhere so I can boot into windows and try some debugging.
Ill check out the repair videos!

Thanks for the suggestions.
And yeah, the card looks kinda baked so I still think that the BGA chip is the culprit but some debugging wont hurt!

What is needed to debug a vga ?

More testing has been done.
I cant get the debugging software to ru or output anything.
Just get a black screen and nothing more, guess its the same problem as when trying to boot.

But! Nothing good but anyway, I did the usual shutdown power on, shutdown power on util the card just happens to run but this time the the screen was yellow. All text yellow and such.
I then proceeded to press on each chip and when pressing the bottom left corner of the bga chip the yellow goes away.
So, almost sure the bga chip is the culprit.

Now, do you guys have any tips on removing the heatsink?
Im thinking that I got nothing to loose to try and reflow the chip.
Got nothing to loose really, if it works then great! I have another card to play with until it breaks again and if it fails, well it doesnt work great as is so...

And I know that just reflowing isnt really that great, all oxidization will remain and it will be temporary but I dont have the equipment or skill for a full reball job.

You can freeze the card if you have what it takes and then twist it in a clock/counter clock way or use heat and thin steel wire to 'cut' the glue ( like the one used for refurbing LCD/OLED screens ) but you have to be careful with that wire ( how you place it ) that thing can go trough textolite/solder balls .

I guess you gave up on this ? :requiem:

Hi.
I havnt given up, just dont have the time at the moment.
I still need to get the heatsink off somehow.
Havnt tried the freezer thing, but I have tried heting it up and cut the glue with wire and that doesnt work at all. Its really hard epoxy of somekind.

have you tried with a cutter blade ? That should be able to pass gently through the thermal glue, like a tiny little "saw" between the chip and the heatsink, ( while pressing towards the heatsink and not the chip of course )

Yes I have, also tried with a scalpel.
Its some sort of epoxy, and it is hard as rock. 😒

This is what i use, i have some leftover from the time i was fixing mobile phones. Be careful, use handles, it cuts skin/flesh:https://www.amazon.com/MMOBIEL-Molybdenum-Cut … n/dp/B01M1KIEYB
This is how it's used:https://www.youtube.com/watch?v=5ei923nq9uw