Random computer freezes no BSOD

[Celerity]

When freezing nothing responds, fans are running but mouse and keyboard and monitor are frozen

It occurs almost at random sometimes it won't freeze for a whole day, sometimes it can't even boot into windows without freezing

I did a memtest (memtest86+) and it went 5 minutes then it froze during that too.

I don't think it's my CPU overheating because it is not overclocked and it stayed at 38c during memtest

My specs are:

CPU: AMD Athlon II Dr 620

RAM: 2x Kingston 2GB DDR3

GPU: Ati Radeon 5570

MOBO: Gigabyte 785GMT-USB3

PSU: A 500W cooler master psu that came. with case

HDD: Seagate Baraccuda 1TB

[Pro_LiZzy]

When freezing nothing responds, fans are running but mouse and keyboard and monitor are frozen

It occurs almost at random sometimes it won't freeze for a whole day, sometimes it can't even boot into windows without freezing

I did a memtest (memtest86+) and it went 5 minutes then it froze during that too.

I don't think it's my CPU overheating because it is not overclocked and it stayed at 38c during memtest

My specs are:

CPU: AMD Athlon II Dr 620

RAM: 2x Kingston 2GB DDR3

GPU: Ati Radeon 5570

MOBO: Gigabyte 785GMT-USB3

PSU: A 500W cooler master psu that came. with case

HDD: Seagate Baraccuda 1TB

Defrag your HDD

Try using Ccleaner to fix registiry issues and clean things you don't need

Check for viruses.

[Aniallation]

RAM: 2x Kingston 2GB DDR3

MOBO: Gigabyte 785GMT-USB3

PSU: A 500W cooler master psu that came. with case

One of these three...

[Mixzzz]

Well try to run stress test and see your cpu temps...