Build a PC Most games crash while playing. Could this be a PSU problem?

I recently upgraded my PC by buying a new CPU AMD 5200+ 2.70Ghz overclocked to 3.0Ghz and all games started crashing.Here's my PC's specs:

Motherboard: Gigabyte-GA69VM-S2
CPU: AMD 5200+ 2.70Ghz currently 3.00Ghz
Video Card: Galaxy GTS250 512MB GDDR3
RAM: 3x1GB Super Talent
HDD: Seagate 500GB
PSU: Fortron 400W
2xDVD-RWs
OS: Windows 7 x86

For example when I start GTA IV the PSU starts making a loud noise and after 15 min the game freezes.Not only GTA IV but Crysis,Metro 2033,Need for Speed Shift...

All temperatures are normal except the motherboard. It was stable until I bought the new CPU. The old one was AMD 4000+ 2.1Ghz :(
CPU:30 to 40 degrees on standby when playing maximum 60
Video Card:45 degrees on standby and up to 65 while playing
Motherboard: 45 degrees on standby and up to 67 when playing
All help would be appreciated :)
 

LinkedKube

Posts: 3,379   +53
Yes it sounds like a problem. The next thing you're going to hear is probably a "pop," if you're unlucky. Upgrade to a quality 450 watt psu or higher, asap.