Windows 8 BSOD and Bios Post problems

I'm having some random crashes in the last couple of days. I'll try to describe the behaviour as best as I can.

Normal pc usage (mostly browsing with chrome, sometimes playing starcraft 2 but never during the crashes). During that, random BSOD with error KERNEL_INDATA_PAGE_ERROR. When this happens, I have the following behaviour:

• If I reset the computer through the hardware reset button, the BIOS POST is extremely delayed (even 30 or more seconds) and then it just hangs there.
• If I just turn it off and then back on, the BIOS works fine and I'm back in windows 8 in a few moments.

After the last crash, I opened up the case. After turning it off and on (reboot didn't work, as described) I heard one of the fans making a strange noise, like running crazy fast. I thought about the video card fan, so I:

• Turned the pc off
• Removed the 2 PCIE power plugs from the video card (a zotac geforce gtx 560 TI)
• Turned on. The noise was still there, and of course pc didn't boot due to missing video card

Then another strange thing. I plugged the PCIE power plugs back into the video card, turned on, and it still behaved like the plugs weren't there (long beep and no video signal). I plugged them off and on about 10 times before it started working again.

I also ran memtest, wmic and chkdsk with no signs of defect on RAM and drives.

Actually I'm a bit confused. My best shots are the power supply (a Corsair CX 750 which is 7 months old) or the video card (which is one year and half old).

But I feel I'm missing something here. Any help would be appreciated, and any suggestion on any more test I can perform to try to find the culprit.

UPDATE

I tried to switch out my VGA with an old one (just old, not broken) and still had the crashes, so I ruled it out.

Feeling like it was either mobo or cpu, I went for the big upgrade.

What I bought new:

• Case
• Motherboard
• Ram
• CPU
• Dvd burner (as new mobo doesn't have ide bus)

What I kept:

• SSD (for windows) and 2 hard drives (for data)
• VGA
• Power supply

And guess what.. crashes still happening. Last one some minutes ago, with the following error:

The computer has rebooted from a bugcheck.  The bugcheck was: 0x000000fc (0xfffffa800b1ccc00, 0x80000002244009e3, 0xfffff803c6cdb650, 0x0000000000000003)

I am really puzzled now. I can't say I have wasted money because the upgrade was very nice, but I haven't solved my problem, nor found the culprit.

Still any help will be immensely appreciated... thanks.

ONE MORE UPDATE

It keeps hanging crashing. I tried to disconnect the two hard drives, keeping only the SSD with windows on it, hoping that it was disk access to an old HDD the problem.

Unfortunately it doesn't seem to be it. After a reboot I got, a few minutes later:

DRIVER_POWER_STATE_FAILURE

So now from the "old computer" I only have the power supply, the vga (that I ruled out) and the SSD... getting closer to the culprit.. but still don't understand what's goin on.