So I am making a build, mid-end. So I've got 6 of the 9 parts. The 9 parts are Intel i5 2500k CPU, Raidmax Tornado Black and Red Steel w/ 450w power supply, intel patriot exetreme master 8gb RAM 1600, GeForce GTX 550Ti, some type of DVD burner, western digital caviar blue 500gb, P67 SLI Micro Mobo, and windows 7
My advice is to never use a power supply that comes with a case. A power supply is a very important choice, ones that come with cases are almost always cheap trash, especially Raidmax. I'd suggest something from Seasonic, XFX or Corsair. (which the latter 2's better models are made by Seasonic anyway)
As far the ability to handle Black Ops 2. All of the COD games, and the new one use the same game engine, its very easy to max out with those specs. You're really spending too much on the CPU and not enough on the video card however, its not the best balance you could get, but if you already have those parts, I guess it can't be helped. But, for your information, stronger CPUs cannot make weaker video cards perform better.
DON'T GET A 550ti!!!! At least get a 560se, it is the same price and is better, the 550ti is a mid range new PC builder trap. But to answer your question if you made the mistake and already bought a 550ti, yes it will run it fine, recommended is a 450.
560 Suck Edition, lol. Forget that. Seriously, the SE doesn't really stand for that, but it should. Nothing wrong with a 550 TI except that you're right, it is an entry level gaming card, but it works just fine. Although 6850s/6870s/7770s and GTX 560 (non TI and non Suck edition) are indeed all better cards in the same price range.
BTW, the 560 SE is just a re-badged GTX 460. My ex had one with an i5-2300. I know its capabilities, I'll put my Zotac 550 TI AMP Edition up against a 560 SE any day.
It isn't a rebadged 460, is has fewer cuda cores. But The 550ti make me mad becuase it is literally the same price for a worse card made by the same company, and yes the 560se performs better than the 550ti, it's "suck edition" because it is a 560 hit with a nerf bat.
I just use hwcompare.com for the ones that are in my price range, but unfortunately I haven't really searched that many cards and got the first one that seemed to fit my needs...
Hwcompare doesn't really give good information on actual performance, it deals largely in theoretical, much like Passmark and Windows Experience Index. As far as the 550 TI, I stand by what I already said. While its definitely not the best video card, even in its price range, and no its not the best to pair with a 2500K, its still perfectly adequate to max out any of the COD games as they are not particularly system intensive. I also stand by what I said, the 560 SE is basically a rebadged GTX 460, which performs close enough to the 550 TI. What 550 TI do you have? If you have one with an aftermarket cooler, you can overclock it. I have a Zotac Amp edition, they pushed the core clock 100mhz over the stock 900mhz, thats about as far as it goes. I think it was techspot that tried to push one further, they didn't get it much further than that.