PC Testing Simulator?

Basically I have an idea for a new computer build I wish to go with, and would like to see how it'd run various games and how it'd do on various benchmarking tests.

Is there a magical site that will allow me to choose every single part imaginable and run a little test with accurate numbers on how this computer would perform ( Frames per second ) various games?

That comparison link Ren gave is a good one, and probably close as you can get. Otherwise, though, you can list your ideas here and we can possibly give estimates for certain games or benchmarks.

Now those are the kind of responses I was looking for!

The games: Skyrim, Diablo 3, Guild Wars 2, Battlefield 3, EVE, DC Universe Online, Kingdoms of Amalur: Reckoning

i5-2310 2.9ghz ( quad core second gen NOT Ivy )
8gb ddr3 1333mhz
1tb 7200 RPM
Sapphire Radeon 7850 OC edition
750 Watt Cool Master Pro Modular
Windows 7 Home Premium 64 bit
1920x1080p 21 inch View Sonic Monitor

How would this build in particular perform those games on 1920x1080?

By the way I tried your link Ren of Heavens, not too bad results with the 7850.

The only game I have personally played from that list is Skyrim. I've played it on a laptop with an i7 2670 (Turboboost to 3.1ghz, but 2.8ghz turboboost if using more than one core, so, it runs at 2.8ghz) and an HD6990m (which is a 6870 core). The 7850 is a nice amount (20-30% faster) better than the 6870 from what I've seen. At 1920x1080, all max settings, it eats it up pretty good even with texture mods. There is one city that was pretty hard on it, but again, everything is at max and that's a high resolution. By "hard on it", I mean it maybe brought it down to mid 20's fps because of trees, fog, and people walking. That rig should play anything you throw at it nicely.

Glad you bumped this, I forgot to check back. I'm sure some of the other guys will know about how it will play, too. It will be a beastly rig.

I don't have the game, myself. It's my brother's. I do know every single option was maxed out, plus he had a few graphic and texture mods. We are gaming enthusiasts, and would rather lose a couple of fps for higher graphics settings, so we always max the graphics :-) He always maxes anti-aliasing if there is an option to do that. Otherwise, he'll force AA in the Catalyst Control Center. I don't know the name of the city it was, sorry, don't have much experience with the game. Other than that one city at that particular moment, it practically played so smooth it had to be 45-50+ fps all the time.

EDIT: The good thing, though, is that his HD6990m is a 6870 core, and the 7850 is supposed to be a nice amount faster. So, I'd put my rep on the line you won't be disappointed with that rig even though I haven't played or seen all of those games. I know Skyrim is hellacious on my Core 2 Duo @ 3.0ghz/HD4870, so a rig like your planned rig is leaps ahead of what used to be a top dog system like mine. And mine can still hold its own in most any new game.

It would be fine for casual gaming. Any HL2 game or mod, CoD:MW2 type game, things like that. That video card won't make you happy with a game that's demanding like Far Cry 2 or Crysis.