Freezing computer, upgrade ?

[hemagoku]

ok so, here is my situation. my pc have been freezing randomly requiring a restart for like 2 years, but the frequency increased a lot during these last 2 weeks. i think the fact that we have a lot of blackouts might have to do with it. now i think there might be something wrong with the computer. i did the ram test and it was ok. as for games i play like only 2 games constantly, League of legends which runs fine most of the time, except like a sec freeze every now and then. And Dota 2, which freezes a bit more than League of legends. (both games on low/medium settings).

yesterday after a freeze i restarted, opened firefox, after like 5min it froze again, i restarted, and when booting up, it got stuck at the motherboard screen for a lot of time, so i restarted yet again and thought i would leave it for the day. and today when i opened up, windows said there was a problem with the computer, please restart or check advanced options, so i restarted yet again. it's working now, but i am getting enough of those restarts.

to clarify a bit more, the computer freezes randomly, even if i am on firefox, facebook or youtube, or anything, not just games.

i am not sure where the problem is, if someone could help with the problem that would be pretty nice. i can consider upgrading too, but i prefer not to expensive, and supporting the new dx12.

my current pc:
gigabyte ep-43-ds3l
intel q6600
ati 4890 xxx edition
4gb ddr2
500MHz PSU

 

[random5]

yeah you should upgrade uhm... entire PC,there's plenty budget builds out there you can get together,atm G3258 +R9 270(X) is on the wave or if GPU isnt that important to you there's always GTX 750 out there which consumes barely noticable amounts of energy.

 

[hemagoku]

any ideas about the problem though ?