Computer started having BSOD's (Windows Ultimate x64)

Hello everyone. :)
My computer started having random BSOD's a week ago (one happened and then downhill from that) but I removed 2 RAM dim's (I have 4 in total) and it apparently stopped for some days. Just 10 minutes ago, another one happened.
Heres my setup:
i5 750 @ 3.2Ghz
2x4gb GSKILL Ripjaws (removed 2x2gb)
Asus P7P55D-PRO
Asus GTX650 TC

Cpu is a bit clocked but it has been for quite some time now and never gave me problems so it can be considered stable.
I had a lot of different BSOD's as you can see, being the latest "NON_FAULT_IN_PAGED_AREA". I hope you can help me solving this situation since I've looked and many people have been experiencing this same thing lately.

Thank you in advance!

(update: ran Error-Checking in C: with both boxes selected and nothing came up. Same with Memtest which ran for almost an hour and 100% pass with 0 errors)

Code:

Host Name:                 HUGO-PC
OS Name:                   Microsoft Windows 7 Ultimate 
OS Version:                6.1.7601 Service Pack 1 Build 7601
OS Manufacturer:           Microsoft Corporation
OS Configuration:          Standalone Workstation
OS Build Type:             Multiprocessor Free
Registered Owner:          Hugo
Registered Organization:   
Product ID:                00426-OEM-8992662-00006
Original Install Date:     16-05-2013, 22:41:47
System Boot Time:          30-07-2013, 00:45:09
System Manufacturer:       System manufacturer
System Model:              System Product Name
System Type:               x64-based PC

Where'd you get your copy of Win7 and how was it activated?