Is there way to lower 12 v usage?

[momonami]

I bought a new motherboard and cpu, Graphics card the same as old build 8600 GT, the problem I have is everytime I use my 8600 GT my 12 v goes from 12.03 to 11.97 and all my games shutdown my pc , I'm using a BFG tech 650 w and don't really understand how I could be having a PSU not enough power problem when i'm just using dual core cpu, 1 dvd/cd rw drive and 1 500 gb HDD. Right now i'm on my onboard graphics card 8300 geforce and it's 12.03 and I dont' crash on any games anymore.

Is there a way to free up some power for my 8600 GT I'm just really angry that I will have to buy 100$ for another 650 watt psu...when this one should be working fine.

Is it possible my 8300 geforce onboard is going the same time as my 8600 geforce, because in bios there is a option called mgpu or something for sli hybrid and it won't let me disable it. I just hope it's not because my 8300 and 8600 are running at the same time or something. I've tried disabling and uninstalling my geforce 8300 but it comes back when install my 8600 cause they use the same driver.

[Gecko]

momonami,welcome to our forum.

I don't think that one 12v rail falling to 11.97v is your problem.
0.03 volts, that's only 0.25% below 12v, well within standard manufacturing range.
It could be that the PSU really is starting to fail and the 8600 maximum draw trips it.

I think it might be a conflict between your on board video and your 8600 causing the crash.
There should be a setting in your BIOS to turn off the on board 8300.
That is where I would start first, changing settings is free.