Games Freezing While Playing CPU/GPU Problems?

Hi, I have a dual core pentium g620 2,6ghz cpu. and gt 440 nvidia geforce gpu, it is freezeing while playing games, sometimes even rebooting itself, i have no bsod or artefacts.
Some times during the freezes i can regain control on my pc after a couple of mins but sometimes i have to manually reset it (if it dosen't do so by itself) now obviously it can only be heat or psu,

I have tested my rams with mem test 46 even tried running the games with seperate ram sticks but still it persists,

**Now my monitor says my cpu is 70c as in 1 core 33 and 37 while idle, it gets to about 90 when playing does this mean its too hot as in 90c for the whole cpu i too hot or would it be too hot when both the cores are like 90?

My gpu during the crashed is about 65c when playing dead island so thats not too bad so im betting on it being the cpu heat, i even installed extra fan it did help a bit as in th crashes are less frequent.

ps i have no thermal paste on gpu/cpu.

The question which i rly want answer to is **

from top thanks ;d

1 More thing - my psu is 430w, the card needs 300w so this is good, however it is 10 yrs old along wit my hdd < i have been using it for like a month as it literarly sat in my old rig for 10 yrs ;p, when the games crash the hdd is red solid and the sound keeps playing in a loop.