Hello everyone, I'm thinking about upgrading my 1.5 year old computer. It works very well - thanks to the bit-tech community, with whom I originally discussed this build in Jan '10! But with some new games on the horizon (Skyrim) I think I'd like a bit more power. Proposed changes in bold. OS: Windows 7 64 bit. Motherboard: ASUS P6TD Deluxe Graphics card: Sapphire Radeon HD5870 -> Another Sapphire HD5870, crossfire Power supply unit: Enermax Revolution 85+ 850W Case: Lian Li Armorsuit PC-P50 RAM: Corsair Dominator GT PC3-12800 C7 6GB (3x2GB) DDR3 -> Another set of 3x2gb corsair HDD: Samsung SpinPoint F3 1TB + OCZ Vertex 3 60gb SSD, OS and Skyrim (lol). CPU: Intel Core i7 920 - not overclocked. -> consider overclocking? CPU cooler: Titan Fenrir I have a few questions that hopefully you guys can help out with: Do you think 2x 5870's in crossfire is a good idea? Or would a single new single GPU be better? What are the rules with adding more RAM to a computer? Does it need to be the exact same type as the first? Further, I can't figure out what my RAM's... "numbers" are. For example 8-8-8-24 (sorry, I don't even know what to call these numbers!). The website where I would likely buy more Corsair Dominator Ram has 3x2gb sets with 7-8-7-20 and another with 8-8-8-24. Do these numbers need to match my current RAM's numbers? And if so, how do I find out what those numbers are? Any other feedback/ suggestions are very welcome! Thanking everyone in advance!