wutang61 wrote on 2023-10-23, 01:40:

I Repasted my FX5900 ultra. Mx-6. checked spread. Good contact all around die via flashlight looking between the cooler and the PCB.

Seeing idle temps in the upper 60’s and load temps near 100c. Is this typical? I can’t remember clearly what they were pre re-paste. But it seems like “idle” should be much closer to ambient than that. Forceware 77.xx.

Mounting is done by the reference plastic push clips. Possible there’s an air pocket on the die?

Take this for what its worth, but "delidding" the die should help quite a bit with temps. Do this at your own risk. I'm not familiar with the 5900 ultra stock cooler and if it's going to make proper contact without the heatspreader. But one thing's certain: that crusty TIM between the die and the heatspreader is adding at the very least 10 degrees celsius.

Honestly I don’t have the balls to attempt to delid the thing. If that goes south, these cards are getting extremely hard to find without paying a fortune.

If it was delided, the stock cooler would have to go or be modified. It’s held by only 2 corners with plastic retainers that clip through the PCB. Similar to Intel stock cooler mounting, but with half the clips.

Photo attached. Quick instant action in mechwarrior 3 back to desktop.

wutang61 wrote on 2023-10-23, 02:24:

Photo attached. Quick instant action in mechwarrior 3 back to desktop.

Sorry I can't help much with the temp question, but what software is that shown?

42C ambient?

wutang61 wrote on 2023-10-23, 01:57:

Honestly I don’t have the balls to attempt to delid the thing. If that goes south, these cards are getting extremely hard to find without paying a fortune.

If it was delided, the stock cooler would have to go or be modified. It’s held by only 2 corners with plastic retainers that clip through the PCB. Similar to Intel stock cooler mounting, but with half the clips.

Try to find a third-party cooler then... Another option is to underclock and undervolt.... Honestly, you're not going to lose much by bringing the core down to FX5800 levels. 400Mhz core is still plenty fast. Install Rivatuner 2.24c.

mockingbird wrote on 2023-10-23, 05:45:

Try to find a third-party cooler then... Another option is to underclock and undervolt....

If the TIM under the IHS has lost its thermal conductive properties, then it is faster to put card on a shelf.

giantclam wrote on 2023-10-23, 05:35:

42C ambient?

Definitely not. Ambient is probably around 23-24c. Makes me think the newer 77.xx forceware is reading the temp probes incorrectly. The system is basically in an open test bench.

The software that is in the screenshot is rivatuner 2.24

how about a finger measurement? you wont be able to hold your finger touching PCB behind a chip at 97C for long

1) Plastic push-pin have a craptastic clamping force.
2) GPU integrated heat spreader has 20 years old thermal paste underneath which needs to be replaced.

Replace stock cooler with ie. Zalman VF900-cu cooler. It should have temps ~70c. Stock 5900u cooler is not that great in the first place and temps go easily to 85c+. Custom cooler should resolve if the problem is between the die and heatspreader or just bad mounting with stock cooler.

I have couple FX cards:
FX5900 (400mhz core) with VF900, 45c idle, 60-65c in 3dm03
FX5900u (450mhz core) with stock cooler, 55c idle, 85-90c in 3dm03

Cards aren't delidded. Haven't really used 5900u for similar reasons. The stock cooling for 5900u is simply inadequate too.

timsdf wrote on 2023-10-23, 12:28:

Replace stock cooler with ie. Zalman VF900-cu cooler. It should have temps ~70c. Stock 5900u cooler is not that great in the fir […]
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Replace stock cooler with ie. Zalman VF900-cu cooler. It should have temps ~70c. Stock 5900u cooler is not that great in the first place and temps go easily to 85c+. Custom cooler should resolve if the problem is between the die and heatspreader or just bad mounting with stock cooler.

I have couple FX cards:
FX5900 (400mhz core) with VF900, 45c idle, 60-65c in 3dm03
FX5900u (450mhz core) with stock cooler, 55c idle, 85-90c in 3dm03

Cards aren't delidded. Haven't really used 5900u for similar reasons. The stock cooling for 5900u is simply inadequate too.

I’ll give that a shot. My gut tells me that it’s a shit mount. Off to eBay we go

Well the cooler (Zalman VF900-cu) came in. Thank you for the recommendation. Just have to grab a few extra ram sinks for the rear of the card (or I might not bother) unsure as of yet.

Mounting pressure was the culprit. Remounted with MX-6. Plugged into an empty fan header on the motherboard with bios settings for all fans set to “slow”

Idles around 35c and peaked at 49c running instant action in mechwarrior 3.

Not exactly a high demand title for this card, but the thermals are very much under control. 95c+ isn’t happening anymore.

If you take off the stock cooler on an ultra, the stock mounting hardware is one time use.

Also, card is absolutely silent now. Just have to ditch the old stock intel cooler next as after 20 years I’m sure that paste is just as chalky.

Thanks for the help guys.