Win7 BSOD during any slightly taxing process

Tech Support Guy System Info Utility version 1.0.0.2
OS Version: Microsoft Windows 7 Ultimate, Service Pack 1, 32 bit
Processor: AMD Athlon(tm) 64 X2 Dual Core Processor 5000+, x64 Family 15 Model 75 Stepping 2
Processor Count: 2
RAM: 2430 Mb
Graphics Card: NVIDIA GeForce 6150SE nForce 430, 128 Mb
Hard Drives: C: Total - 305234 MB, Free - 148764 MB;
Motherboard: ELITEGROUP, MCP61PM-AM
Antivirus: avast! Antivirus, Updated and Enabled

If this is the wrong section, I apologize in advance.

Lately, I've been getting BSOD's whenever I do something that uses a moderate amount of resources. (Gaming, media streaming, etc..) For instance, I'll be playing a game when suddenly out of nowhere, a BSOD pops up and gives me a 124 stop-code, which i believe is a hardware related code but i'm not sure. One out of my two internal fans does not work (the one attached to the side of the case), so I'm using one external fan aimed directly at the motherboard.

My uneducated theory is that every time it gets to a certain temperature inside and TRIES to spin that broken fan but can't, it think's something's wrong and crashes...?

Any help would be MUCH appreciated
Thanks in advance.