Software readout of voltages are not always accurate. The only means to know the true voltage is via a digital volt meter or O-scope. Your BIOS seems to indicate that the 12v rail is OK and it's probably correct. You could try running an OCCT stress test to see what it shows for voltages and CPU core temps under stress as it records the voltages, temps and frequencies.
There are many reasons why a PC can freeze. The FX-8350 is a high power demand 8-core CPU. Gigabyte has had mobo VRM issues with the 8-core FX CPUs as their VRM circuits were not designed to handle these heavy power consumers. The Rev. 5 model of the GA-990FXA-UD5 is better than the prior Revs. as Gigabyte redesigned the VRM circuit.
That being said assuming that you have the correct BIOS version installed to support the FX-8350, I'd run Memtest86+ V4.2 or V5 overnight to be sure you don't have some RAM issue causing the freezing.
It's highly unlikely that there is an issue with the CPU unless it was physically damaged when you removed it from the box as these CPUs are fully tested just prior to boxing for shipment.
Technical ignorance is NOT a destiny it is a choice. Do your homework so that you can make technically informed decisions and not be duped by advertising hype or mis-information stated as fact when its not.
09:23 AM by