I am planning on using a 64-bit system. I will first use an old key for vista I have lying around, but will eventually move onto Windows 7. I am actually planning on getting on getting two of these cards in a SLI configuration or crossfire, but the second card will most likely be my birthday present in a month. I have never done it before and I figure 2 mid-high range card would let me try it out. After reading I may bump down the RAM to just one set and save myself $110 for now, but I do tend to run multiple applications. I do a far amount of mathematical/ graphical models. I run Autodesk modeling software and MATLAB at the same time on some occasions. I figure I could always get one set of DDR3 memory and then upgrade when the price drops a little. This will actually be my first build so if you got any tips for a first timer I'm all ears. Here is the case I picked out it has 6 fans and a good amount of space.
NZXT Tempest ATX Mid-Tower Case - Clear Sides, Front USB, eSATA Ports
[url=]http://www.tigerdirect.com/applications/searchtools/item-Details.asp?EdpNo=3911521[/url]
EDIT: I want the SLI, because I like to run my computers at high resolutions. The laptop I have now runs at 1920 x 1200 and I want to keep it that way.

Given that additional information I'd say all your choices are spot on; you've obviously put quite a bit of thought into component selection. And nice case.
EDIT: As for tips for a builder, the main thing is to make sure you ground yourself before handling components; you don't need a grounding strap if you don't have one on hand, but touch a grounded piece of metal, such as a faucet, to discharge any static before handling components (CPU is the one you need to take the most care with). As long as you take your time and consult the mobo manual to see where each cable attaches everything is pretty straightforward. The one exception can be seating the CPU fan/heatsink; some of these can be an absolute pain in the ass to mount, and the only real advice is to just be patient and try to keep your cool (if it proves particularly difficult take a break, calm your nerves, and come back with steadier hands). Also check the components are working once it's all put together and running; make sure the CPU is running at the right speed (I've run into a few that came underclocked), and also test the RAM with something like memtest (this can save lots of time with trying to track down the source of crashes if it turns out you were shipped a bad stick of RAM). And enjoy yourself, putting together a computer should be fun.

Yeah I have used GPUZ before so testing the speed will be easy. I have never overclocked considering I have been using my laptop for the past 3 years. Any advice on that? I know to watch out for overheating and the occasional instability.
P.S. - It took me forever to pick these parts out. I must have switched out each part twice before I settled on it. The past three weeks have been reading forums and reviews for at about 2-3 hours a night. I am going to really enjoy this. :)

Basic overclocking (for both CPUs and GPUs) is actually pretty simple. For GPUs it's simply a matter of raising the core clock speed in increments of 20-40 MHz (most all GPU utilities allow you to do this- pick your favorite). Stress test a bit after each increase, watching for instability, temperature, and artifacts; if you observe any just drop back to the last stable clock speed. With CPUs the procedure is the same, but instead of changing the clock speed directly you'll need to change either the CPU bus speed or the multiplier (some motherboards have one of these locked, so just change the other one); this can be done either through the BIOS or through some utilities. The bus speed and multiplier can only be changed in discrete increments, so pick your favorite and just increase it one unit at a time, again stress testing after each increase.
There's also more advanced settings you can change, such as the CPU voltage, or the RAM timings and voltages, but unless you already feel quite comfortable with overclocking and want to get every little last bit of possible performance out of your hardware I'd recommend against tweaking these things, as this is where you can actually end up damaging your hardware (the only danger with basic overclocking is if you make way to big a jump and cause your hardware to drastically overheat).

Thanks for the help +1 for everyone. Hopefully the setup goes smooth. I will probably be putting it together in 2 weeks. If I can wait that long...

Seeing as we have one happy user here, I might as well hijack this thread. I'm thinking of upgrading my grahpics card. I have an 8800 GTX, but I want to get a GTX295, mostly for ARMA2, which I hear strains the 8800. So, my question is, is it worth it to just get two GTX275s in SLI, or just get a 295? And can I SLI with my 8800GTX and my GTX295?

It depends on what games you expect to play, and whether you are playing at very high resolutions (say 1900x1200 or above). Some games work better with SLI than others, and in all cases a single card gives more reliable, linear performance than multiple cards. Connecting two cards together never doubles performance. You may find you get better results with a single card (even if it is ostensibly less capable than an SLI pair), especially if it ends up being cheaper that way. If you are playing at very high resolutions, SLI can provide an extra performance kick without you having to buy a more expensive single card to achieve the same result.
Unless something has changed recently you cannot connect your current card in SLI with a newer card; all SLI cards must be the exact same card model (I don't think the same restriction applies to ATI's "CrossFire" alternative).

The "SE" board has support for ATI CrossFire but not Nvidia SLI. This only matters if you plan to run multiple Nvidia cards linked together via SLI; if you plan to stick with ATI for the life of this motherboard and/or would only have one Nvidia card at a time anyway feel free to go with the "SE" model and save a bit of money. Multi-GPU motherboards tend to be a bit more expensive; if you don't plan on having more than one video card at a time you might find you can get a single-GPU motherboard and save a bit of money.

Two identical cards are required for SLI. Also, you'll typically only see a significant benefit from SLI at higher resolutions; if you're not running at particularly high resolutions then you'll get a much better performance/price ratio with a single powerful card compared to two moderate cards. The 295 GTX is also obscenely overpriced, and in addition won't really distinguish itself from the likes of the 275 GTX until you get beyond 1900x1200 resolutions (basically up to that point they'll both run every game out there easily). Also, unless the rest of your machine has specs similar to what PieceMaker42 is putting together it's likely either your CPU or RAM will end up bottlenecking the 275 GTX a bit, to say nothing of the 295. Finally, make sure you actually need a new card before you go out and buy one. Despite its age, the 8800 still handles most games quite well, provided you're not cranking the resolution or the anti-aliasing. Make sure you're not dropping several hundred dollars to solve a performance problem that doesn't even exist.

I actually just noticed that the card I am thinking of getting doesn't support 1080p technically. Should I spring for another card or does it even matter that much?

If you were still thinking of getting this card then you would have 1080p support along with HDCP support which is necessary for blu-ray playback.
from the source:
Integrated SD and HD TV Output
World-class TV-out functionality via Composite, S-Video, Component or
DVI connections. Supports resolutions up to 1080i/1080p, depending on connection type and TV capability.
HDCP Capable
Designed to meet the output protection management (HDCP) and security specifications of the Blu-ray Disc and HD DVD formats, allowing the playback of encrypted movie content on PCs when connected to HDCP-compliant displays.
Even if it didn't have an HDMI connector it supports HDCP over a DVI link.
With the nvidia card you're also getting hardware based acceleration and [url=http://www.nvidia.com/object/cuda_home.html#]Cuda support for leveraging the parallel processing capability of the GPU for CPU intensive operations in applications that support Cuda (i.e. encoding H.264 HD content in real-time or faster).
Personally I think those 2 extras are worth the few extra bucks for the nvidia card. But if "bang for the buck" and "frames per second" are your only concern ATI is the way to go.

Even though nvidia doesn't support hybrid / asymmetric SLI you can still get use out of your old 880GTX by setting it as a dedicated PhysX accelerator if you have an SLI motherboard.

No point in keeping such a good card only for PhysX.
And on topic if I were you I would but at least 260gtx 216sp - anything lower is just G92.

How important is the video RAM, it would be a step down from 1 GB to 896 MB. Is difference enough to effect much?

Depends on the type of games you're running. VRAM really comes into play when you're dealing with high res textures. However, going from 1 GB to 896 MB, if all other things are equal, won't result in any kind of noticeable difference in performance unless you're already taxing your card to its limit. The amount of VRAM is also very rarely the limiting factor on a card when it comes to overall performance.