the 5-5-5-15 is in terms of speeds of things, and latency and its high. And there are plenty of 4-4-4-12 or even 3-3-3-9 CAS ram sets available for cheap.
The x48 and E8400 is allot faster than the AMD build. Also the Rampage Formula supports crossfire so I would get the HD4850 and have the option of adding a second one later.
i think im going to stay AMD mainly my friends are all amd and if we need to swap parts to debug its just easier
also i hear the 4850 overheats really fast any alternatives to cool that bad boy? no water cooling thats out of my budget. i couldn't find a good after market fan actually i couldn't find one at all.