Blue Screens

Hey there,

Unfortunately, I am 100% clueless as far as software/hardware problems go, so please be gentle.

So I've had several blue screens now. To me it seemed to happen at random times, usually about half an hour to an hour after I restarted the computer.
The only program that was open during all of the blue screens was Firefox.

I wrote down the message, Windows spit out:

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A problem has been detected and windows has been shut down to prevent damage to your computer.

A process or thread crucial to system operation has unexpectedly exited or been terminated.

...
(Some not very useful tips)
...

Technical information:
*** STOP: 0x000000F4 (0x0000000000000003,0xFFFFFA8009A005A0,0xFFFFFA8009A00880,0xFFFFF8000035DE4 66)
---

My computer specs (copied from TSG SysInfo):
Tech Support Guy System Info Utility version 1.0.0.2
OS Version: Microsoft Windows 7 Home Premium, Service Pack 1, 64 bit
Processor: Intel(R) Core(TM) i3-2120 CPU @ 3.30GHz, Intel64 Family 6 Model 42 Stepping 7
Processor Count: 2
RAM: 8175 Mb
Graphics Card: NVIDIA GeForce GTX 550 Ti, 1023 Mb
Hard Drives: C: Total - 61056 MB, Free - 8962 MB; D: Total - 1430796 MB, Free - 922545 MB;
Motherboard: Gigabyte Technology Co., Ltd., H61M-D2H-USB3
Antivirus: Avira Desktop, Updated and Enabled


I googled a bit and now I think it might be my RAM?
If so, how do I check for it?

Any help is much appreciated,
Lum