Hello! I have the GIGABYTE P55A-UD4P rev. 1.0 motherboard (specs here), but my huge copper CPU heat sink is covering one of my 4 RAM slots. So currently I only have 2x2GB of G.Skill DDR3 memory. It has been sufficient for the past two or three years, but some of my software programs are utilizing up to 97% of my memory now, which means it is time to upgrade. To this end, I have several questions. First, I vaguely recall reading (years ago when I first built my system) that I needed an even number of sticks. In other words, I have this notion (whether true or not) that using 3 slots and leaving the fourth empty wouldn't work, or, at least, wouldn't utilize the stick in the third slot. I don't recall whether this was a restriction due to my operating system or due to the motherboard, or even if I just imagined this whole idea up out of nothingness, so I'm hoping one of you might assist me through helpful explanation(s) and/or elaboration(s). Second, a friend recently suggested my motherboard might not be compatible with 4GB sticks, since 4GB sticks (according to him) didn't exist back when my motherboard was purchased. I have no reason to doubt his suspicions, but it'd be wise of me to find out for certain before purchasing any new RAM. Would anyone please verify for me whether my motherboard can handle 4GB sticks of RAM? If it is a matter of BIOS version, I should note that I recently tried updating my BIOS but the latest version (F14) available on GIGABYTE was incompatible (it gave me an incompatibility error when I tried double-clicking the setup/installer file). Lastly (for now), I recently purchased an RPG game called The Witcher 2. I'm wondering if any of you hardware guru's or tech-savvy deities might have some recommendations with respect to a video card upgrade which would be most appropriate for CD Projekt Red's "Red Engine" (the game engine created specifically for The Witcher 2 PC game). For the record, my current video card which I wish to replace is a Radeon 5770 (which seems inadequate to perform well with high graphics settings). Thank you all in advice of your kind support.