Originally Posted by Nisrock7863
I've hit a bit of a snag...I'm still at 4.4GHz, haven't changed a thing, but had a weird lock up while playing some Dishonored. Following said lockup, I rebooted and started tinkering with IBT AVX. I'd previously run it at 4.4GHz with the same voltage at the same settings (very high) for 20 passes with no problems. It failed within two passes and speed results that were lower than I'd previously seen. I upped voltages three or four times trying to find stability before I had a lightbulb moment and shut the computer all the way down, then fired it back up again. It passed twenty times with no issues, and with speeds that were more in line with where they should be.
I decided to do a little experiment. I'd read (I believe in this thread, actually) that running IBT AVX or Prime95 with Unigine Heaven at the same time will heavily stress the power supply and check its stability, so I did just that. Within five minutes the machine locked up again. Heaven has never given me any trouble before. I've run it for hours with the settings I'm currently running my GPUs at with no hickups. I've also run IBT AVX for extended periods of time with no problems.
What are the odds that my power supply is choking, or defective? It's a Corsair CX750, running an FX 8320 OC'ed to 4.4GHz at 1.356v on an Asus M5A99FX Pro R2.0 motherboard. My GPUs are two MSI GTX 660s with just a 200MHz bump to memory. My hard drives are an 256GB Samsung Pro SSD and a 7200RPM WD Blue 1TB HDD, and the only other draw (fans aside) is a DVD drive that never sees any use. According to the calculator I used I'm well within the voltage level provided by this power supply. It's only a few months old, but I'd previously noticed that it made an odd squeaking sound that got louder under heavy load. Maybe I need to RMA it.
Any suggestions would be greatly appreciated.
You are not within the voltage
level of the PSU. I should point out that the bold item should be changed to POWER.
What calculator did you use? I should also point out that you should never base your calculations from stock values. you have overclocked your CPU by 26% that should also increase it's power draw (CPU Alone) by 26%. Add in a bump in the Voltage, your Power Draw (for CPU) goes further. Same as with your GPU. So I reckon you are way above 30% of power in terms of increase to consider.
The sound you hear could be coil whine. Or fan noise. Note that PSU ramp up their fan speed according to loading as loading is directly responsible for it heating up.
SSDs, HDDs, DVD Drives, Memory, and Motherboard Power draw could be neglected individually but sum them up and you have something.
You can check your power draw from the wall socket to confirm if your PSU rating is not enough for your rig though. If it pulls more or within -15% of 750 Watts, you need to buy a higher rated one. Edited by mus1mus - 4/9/14 at 3:02am