You mention that your parts cost you $700. You also mentioned that you already have Windows 7. I noticed that you wanted the 965 black edition processor. If you are willing to, I am honestly suggesting you go to www.cyberpowerpc.com. They currently (and always) have really amazing sales going on. I just clicked on their main customization thing, and I clicked on the first computer.
After picking a different case, it is $858, with a $10 rebate on the case ($848 total). $9 will get you anti vibration mounts on the fans, which are nice if you really want quiet ($857 total).
The current processor, as you will notice is the six core 1055T, which is 2.8 GHz I believe, but faster than the 965 black edition that you are interested in.
You get 1 of 2 free games with this system. The first is STALKER. If you aren't interested in this game, you can make ~$15 selling it on amazon ($842). The second game is Dirt 2. ~$15 more if you don't want and just sell it.
This system, along with basically everything on CyberPowerPC comes with liquid cooling along with fans.
Comes with 4 GB of 1600 memory, which is what I noticed you are interested in.
As for the graphics card, this systems card will blow you away. It is an ATI Radeon 5770.
With that card, you get yet another free game. Blacklight: Tango Down. Can't find it on Amazon, but i'm sure you could sell it for a little on Ebay if you wanted. At least $5 ($837 total).
With the AMD processor/graphics card combo, you also get the game Stormrise. This game basically has no resale value, but its still a free game.
System comes with a 1TB (7200 rpms) hard drive, so I guess you can sell your current ones.
Comes with some crappy speakers, take them off for $5 ($832 total).
I'm assuming you don't need a keyboard or mouse, so that's $7 more back ($825 total).
Comes with a flash media writer, which you may or may not need, get rid of that for $3 ($822 total).
Total is $822 for a computer that is way above and beyond the one you will spend $700 on. That's only $822 extra, plus you could probably sell your 2 hard drives.
Also, if you want to make it cheaper, they sell you Just Cause 2 for $9.99 and you can make ~$20 on amazon selling it, making the total system cost $812. Free shipping.
Honestly, ever since I discovered this website, I determined people are basically fools to build their own system when this site makes amazingly reliable computers for cheap.
Also, no, I'm not some representative of the site, I'm just bored and really did all of this work just for you.