Windows 7 numerous BSODs

Ill try and keep this short. March 16th I bought a new Core i5 750, ASUS P7P55D and GSkill F3-10666CL9D 4Gbs. I also wiped and reformatted my HD and installed a fresh windows 7. I installed all my drivers from my mobo disk, then downloaded the most recent ones from the AUSUS website, my graphics card drivers and my Logitech G15 and G5 mouse and keyboard drivers. 4 days later i started with my first BSOD which i have included and have had numerous since. I have made a list of the blue screens i have gotten:
Memory_Management 0x1A (being the most frequent)
Bad_Pool_Header 0x19
Bad_Pool_caller 0xC2
PFN_List_Corrupt 0x4E
IRQ_Not_Equal_or_Less
Page_Fault_in_non_paged_Area

These are all during the bootup. Right around the Welcome screen, little before or a little after. All around that time.

I read around a lot looking for an answer. Most sources pointed to bad RAM. I ran memtest86 on each of my 2GB sticks separately and left them over night for 25 passes each. Came back all clean for both. Alot said drivers, but I'm sure I updated all of mine. I also have had the problem with files on my HD becoming corrupt as well. All Windows updates as well and have tried system restores and usually lead back to the blue screens.

I have another hard drive that i installed Windows 7 on to try. And same problem a few days later once I install everything. I made a list of my steps I took.

-Install Windows
-Install motherboard drivers from the Disk/Nvidia (for my graphics card)
-I would then download the newest once from ASUS

Then after the comp restarts to finalize all the drivers updates I would install all my other programs: Xfire, Steam, Firefox, Itunes, Limewire, Logitech mouse and keyboard drivers, AVG, Ventrillo, Call of Duty Modern Warefare 2 and World of Warcraft and thats it.

Sorry for the long read, I am just to the point where I'm getting frustrated and need help. Thanks in advance and thanks for your time

Edit: Thought I should put other information about my PC:
-Core i5 750 (Not overclocked at all, With a stock cooler)
-Asus P7P55D
- GSkill F3-10666CL9D 4Gbs
- XFX 8800GT 512MBs
-Corsair 750W PSU
- Western Digital 250GB HD (I have 2 of them, different models)
- CD Drive of course

Any ideas

Start buy downloading Memtest86.com - Memory Diagnostic and run it, tell us how it goes.

I ran memtest on each stick individually, which came back clean. ill try them together. I dont know why i didnt do that before lol. Ill let ya know the results when i get home.

When I came home, Memtest reported lots of errors with a confidence value of 18. It showed 999999998 errors on slot 1 and 2 on slot 2 on only the 2nd test. While I was in class i was looking around the GSkill forums and lots of people have the same setup I do and had some of the same problems. The techs there recommended turning on XMP in the BIOS and turning the command rate/Timing from 1N to 2N and at the moment my computer has rebooted and started up just fine. Ill post back if anything changes.