PC shut down ingame/Nvidia driver crashing

[MagicALCN]

It's really a mystery...

I got a Zotac GTX 980 Ti extreme since 2015 and this card is just a beast and draw a lot of power. Until 2020, I only got Nvidia drivers crashing rarely but it wasn't a big deal...
But since a month, my PC just shut down after few minutes on OCCT, 100% TDP (~300W). But the card is working normally, it just that after like 20 minutes in a game, the PC shut down without any reason. (It shuts down after 5 minute on ff14 at 285W TDP). I though that it was just my power supply (650W and it's at 90% since 2015) so I just replace the bios of the 980 Ti by a custom one (1.1GhZ instead of 1.4GhZ and 225W TDP) and now the card lost like 5 to 10fps in ff14 and now draw 170W but it shuts down after 15 min...

I'm using a GTX 1070 with memory issue now to play games at 100W and it's okay for now. Its only at 45% TDP in ff14, it's weird because it's on the same settings and the 980 Ti was at 80%-100% TDP

I really don't know if it's the power supply because I put a 5870 Matrix in there (400W TDP) on OCCT and it pass the stress test... 

 

 

Any Idea ?

[cr8tor]

Please list your system specs, include model numbers when possible.