First off, the RAM kit I bought was a four stick set (purchased off Newegg).
I updated to the latest BIOS available for the Z87 Pro, 1707. I'm still unable to boot up whenever I put any sticks in the A1 and A2 slots. However, the issues I'm encountering are a bit different now. Now, with XMP disabled, when I boot the LED goes through a bunch of codes, flashes 03, then the whole computer shuts off, before rebooting, going through the codes, and crashing again. Previously, I would encounter this issue when placing two sticks in B1 and B2, and one into A2. It seems though that the motherboard is getting past the 55 code now. The last code that is flashed now before the computer shuts off is 03.
As for the fan, I reseated it, and I don't think that it's the issue. My CPU runs at 19-22 celsius when idling.
Also, I've seen online that maybe I should try boosting my RAM voltage to 1.55V? Is this advisable? And how would I go about setting that up?