Loganius wrote on 2023-05-18, 03:38:

I just got an nVIDIA 7900 GTX for my overpowered 98 machine. I'm using the 82.69 driver and everything is working fine except fo […]
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I just got an nVIDIA 7900 GTX for my overpowered 98 machine. I'm using the 82.69 driver and everything is working fine except for the fact that my card has been down clocked into oblivion and I get this error message on boot:
"The NVIDIA System Sentinel is reporting that the NVIDIA-powered graphics card is not receiving sufficient power."
This, despite the fact that I definitely have the 6 pin PCIe power plugged in and I have a 500w PSU.
I have no idea what is wrong and need help. Or rather, I suspect the card has been damaged, either in shipping or from the seller, but I can't find anything visually wrong with the card. (And I'm in denial.)

Set all power options in high performace on driver and on windows. HWINFO is your friend to check if all is correct

That error indicates bad connection in 6-pin plug.
Either on cards end (pin inside 6-pin are crushed/bend), or PSU plug side has trouble with wires (going into plug).
Lastly PSU may have deteriorated capacitors that can't sustain stable power under heavy load.

I recommend checking 24-pin ATX as well, for any signs of pins being loose or cables sliding out.

Loganius wrote on 2023-05-18, 03:38:

I just got an nVIDIA 7900 GTX for my overpowered 98 machine. I'm using the 82.69 driver and everything is working fine except fo […]
Show full quote

I just got an nVIDIA 7900 GTX for my overpowered 98 machine. I'm using the 82.69 driver and everything is working fine except for the fact that my card has been down clocked into oblivion and I get this error message on boot:
"The NVIDIA System Sentinel is reporting that the NVIDIA-powered graphics card is not receiving sufficient power."
This, despite the fact that I definitely have the 6 pin PCIe power plugged in and I have a 500w PSU.
I have no idea what is wrong and need help. Or rather, I suspect the card has been damaged, either in shipping or from the seller, but I can't find anything visually wrong with the card. (And I'm in denial.)

"500W PSU" doesn't mean much. Which PSU brand are you actually using? That warning can appear when the card detects unstable/unreliable power delivery, which is a very common occurrence with cheapo (or damaged) power supplies (even if they appear to be in working state at first glance). So, first things first, I would suggest trying a different PSU from a known good brand. I would also try it with another motherboard in WinXP, if possible (Win98 drivers for such a new card can be very finicky). If you still get the same behavior, then the video card is most likely faulty.

Gumur.gurl wrote on 2023-05-18, 05:01:

-get one of those pcie 6 pin adapters. i have never trusted 6 pin directly from power supplies.

Uhm... wut?

Gumur.gurl wrote on 2023-05-18, 05:01:

-use beta drivers, they are not very picky about power, i have 2 nvidia quadros and they are PITA about power. YOU KNOW FORCED obsolescence PUSHED BY jensen.

Even if it does work, this 'fixes' the effect, not the cause. 😉

bloodem wrote on 2023-05-18, 05:15:

"500W PSU" doesn't mean much. Which PSU brand are you actually using? That warning can appear when the card detects unstable/unreliable power delivery, which is a very common occurrence with cheapo (or damaged) power supplies (even if they appear to be in working state at first glance). So, first things first, I would suggest trying a different PSU from a known good brand. If you still get the same behavior, then the video card is most likely faulty.

I'm using a few year old EVGA 500w bronze. I was previously (until today) using a roughly year old 400w EVGA power supply, when I swapped it out for troubleshooting. They both had the same error.
Also, before I got the 7900GTX, I had been using a 7950GT, which never complained (assuming I remembered to plug in the PCIe power.) In fact, I've swapped back in the 7950GT for the time being, and it's working perfectly.

agent_x007 wrote on 2023-05-18, 05:03:

That error indicates bad connection in 6-pin plug. Either on cards end (pin inside 6-pin are crushed/bend), or PSU plug side has […]
Show full quote

That error indicates bad connection in 6-pin plug.
Either on cards end (pin inside 6-pin are crushed/bend), or PSU plug side has trouble with wires (going into plug).
Lastly PSU may have deteriorated capacitors that can't sustain stable power under heavy load.

I recommend checking 24-pin ATX as well, for any signs of pins being loose or cables sliding out.

For what it's worth, I poked my multimeter into the solder joints coming from the 6pin connector while the system was live. I read 11.92v between the 12v pins and the ground pins.

Loganius wrote on 2023-05-18, 05:27:

agent_x007 wrote on 2023-05-18, 05:03:

That error indicates bad connection in 6-pin plug. Either on cards end (pin inside 6-pin are crushed/bend), or PSU plug side has […]
Show full quote

That error indicates bad connection in 6-pin plug.
Either on cards end (pin inside 6-pin are crushed/bend), or PSU plug side has trouble with wires (going into plug).
Lastly PSU may have deteriorated capacitors that can't sustain stable power under heavy load.

I recommend checking 24-pin ATX as well, for any signs of pins being loose or cables sliding out.

For what it's worth, I poked my multimeter into the solder joints coming from the 6pin connector while the system was live. I read 11.92v between the 12v pins and the ground pins.

What about during sustained heavy GPU load though? It's still plausible that you are experiencing a voltage drop or ripple if you haven't monitored voltage during load.

Loganius wrote on 2023-05-18, 05:27:

For what it's worth, I poked my multimeter into the solder joints coming from the 6pin connector while the system was live. I read 11.92v between the 12v pins and the ground pins.

You mast check connection from connector to mosfet at the drawn card. Most likely there is inductance.
And check the connector pin that goes to the voltage sensing circuit.

I think we found the culprit.
I believe these were capacitors on the power management side of the board (as in the side near the 6pin connector)

Auch, that looks like three capacitors are gone and two transistors. C504, c587, c576, q515 & q519

weedeewee wrote on 2023-05-18, 21:45:

Auch, that looks like three capacitors are gone and two transistors. C504, c587, c576, q515 & q519

Welp, I think we have our answer.
I didn’t even notice c504.
I noticed it appears one of the pads on q515 was ripped off. When I saw that, I decided to just give up on repairs and just return it. Currently in the process of doing that.
I mentioned in my first post I suspected damage.
My suspicions have been confirmed.
Thanks for all your help everyone. If anyone is selling/sees a good deal on a replacement 7900 GTX, please let me know. Otherwise, I’m calling this case solved.

Side note: I’m new to posting on Vogons. Is there something I’m supposed to do to close the thread?

yep, disgausting storage