Drives keep disappearing and constant BSoDs

Running Windows 7.

My specs:
MB: Asus P8P67Pro
CPU: i7 2600k
RAM: G.Skill Ripjaw (2x4GB)
PSU: PC and Power Cooling 750W
Cooler: Artic Cooler Freezer 13
Sound: HDA XPlosion'
Graphics: ATI Radeon HD 6870

DVD: Pioneer DVD-RW/DVD-R 212D
HDD: Western Digital Raptor (150GB)
HDD: Hitachi Deskstar (400GB)
HDD: Hitachi Deskstar (750GB)
HDD: Hitachi Deskstar (1TB)
HDD: Hitachi Deskstar (1TB)

BSoDs:
STOP: 0xF4 (most frequent)
STOP: 0x7E
STOP: 0x7A
missing %hs

I recently built a new computer. There were no problems putting it together but when I tried to install Windows my drive kept disappearing. I only had one drive plugged in at the time (Western Digital 150GB) because I heard about people having trouble installing Windows with multiple SATA drives.
Eventually, I got the system to recognize the drive long enough to install Windows and l was up and running for a while. However, over the past few days I have had countless crashes all resulting in Blue Screens, different ones at that.
I reckon the problem is that the C: drive keeps disappearing and Windows can't find it so it throws out a BsoD relevant to it at the time.
The weirdest part is sometimes when I go into the Bios any number of my drives will not be detected but after a Simple reboot they'll be there again. The only drive that is always there is my DVD drive. The only problem with that is I can't seem to boot from my DVD drive at all, not even to boot from my Windows disc.
The problems have been getting worse. lt is a war to get into Windows now and if do manage to get in, its only a matter of time before it crashes again. I have discovered l cannot run Avira, my sound will suddenly disappear and copying /moving /downloading will cause it to Blue Screen without fail.
I have since reseated all components of my computer, I have turned off drives going into hibernation, I have changed all the Sata cables and can verify the integrity of all my drives. Everything, especially when it crashes, seems entirely random to me. I am at a loss as to what to do. I have tried everything I can think of and I am running out of ideas.
Any help would be greatly appreciated, thank you in advance.

 

Sounds like you've done everything I would have done. I would think that you have a bad mobo and it's RMA time. I have the same board and love it, but I know you didn't want to hear that.

 

Well, that sucks but its good to get a second opinion. I kinda figured it was the case. Thank you very much for the rapid reply. I really appreciate it.