1 out of 6 NVIDIA 3080 GPUs start normal then back down to 200 watts

[thisisjustforfun]

I have one 3080 GPU that will run at 97 MH/s for about 30 seconds then slowly backs down to 87 mh/s (exactly 200w). Its using the same settings as the other 5 cards but I have tried many changes to each without success. I tried using multiple fans to try and cool better and the temp is lower than the good cards. Here is a summary of my config:

Driver version = 465.31 (tried previous versions too)
Miner = PhoenixMiner 5.6d
Core = -200
Memory = 2000
Power limit (pl) = 225
Kernel = 5.4.0-hiveos #108
Motherboard = TB360-BTC PRO BIOSTAR
Memory = 16 GB

[rkwjunior]

Its most likely thermal throttling.
You may have to change out the thermal pads

What model 3080 is it?
Also, id dump pheonix miner and use NBminer or Gminer, they are both way better in terms of hashrates and wattage.
Also, use absolute core clock settings.
1060 core
2275 memory
and 0 power limit.
I run 99.6 MH at 214 watts on NBminer.
Set Ur fan auto setpoint to 50c and let Hive control the fans

[thisisjustforfun]

Thanks, rkwjunior! I really appreciate the suggestions. I ordered the thermal pads and will give those a try along with your setting suggestions.

[thisisjustforfun]

Hello rkwjunior. I wanted to quickly follow up with you in particular on this as you took the time to give me some good info on this and other messages. I purchased 1mm thermal pads and redid the stock RTX 3080 ones. It looked like it wasn’t going to work with 1mm as the hashrate dropped to ~50 Mh/s however doubling up them to 2 mm was successful! That card is hashing in line with my other 3080 cards now.

Thank you very much!

[rkwjunior]

Good, im glad it helped.
I actually have never changed thermal pads before myslef, but i know its a known issue.
The 3080s can be finicky for mining.
Happy hashing