Help please, computer has started locking up

[trooper1822]

Hello,
Recently my computer has been locking up. Started doing this about a week ago. Under normal usage such as surfing the web or normal tasks it is fine. But when I try to play some games on it that put it under load it will just freeze and the only way to reset it is to hard reset. I have tested the memory using the win 7 tool and also using Memtest86+ and OCCT and it passes every time. I also tested the GPU using OCCT and also by replacing it with a new one that I just bought and it is fine. Every time I try to torture test the CPU it runs in OCCT for about 3 min and then locks up. I am starting to lean towards the motherboard has gone bad but dont want to buy a new one until I get some advice. Thanks for any help

Windows 7 64bit, OCZ Platinum 4GB DDR3 RAM, GeForce GTS 450 1GB, MSI 790FX-GD70 AM3 AMD Motherboard, AMD Phenom II X4 965 Black Edition 3.4GHz (OC 3.7), Corsair H70 liquid cooler

 

[OhSnapWord]

Check the hard drive. A bad drive will cause lock ups.

 

[rafwraf]

How old is the Computer. Is it still under warranty ?

 

[trooper1822]

How old is the Computer. Is it still under warranty ?

it is a home built computer. I built it back in Nov 2009.

 

[setishock]

Time to redo the thermal paste on the cpu to heatsink connection. Hot will lead to lock.

 

[Indigo]

You're overclocking - general rule #1 when it comes to overclocking - drop your clocks and timings back to base settings to isolate issues with the system - if the issues persist, dig deeper.

Heat is a possibility, but while you list the specs for your system, you haven't mentioned which power supply it is. I don't trust software to do true and accurate diagnosing of a power supply - they can look at certain metrics sure, but for the most part, you need to test the unit yourself, physically (and manually) with the right equipment to get a real idea of what's going on in there.

Since you've already run MemTest, you've got that base covered at least.