I'm planning on ordering a sandy bridge based system from AVAdirect in a couple weeks. I have a budget of about $900 before shipping, and I want something I can use for basic gaming but I have no desire for multi-GPU systems or overclocking. I simply want to be able to play new games coming out in the next few years (such as Elder Scrolls Skyrim which given Bethesda's record is going to push hardware). I plan on using a 20" LCD (1280x1024) and/or a 32" HDTV at either 720p or 1080p. I know I can save money building my own but I just can't right now. Here's what I've come up with so far.
* COOLER MASTER Centurion 5 II Black/Silver Mid-Tower Computer Case w/ Window, ATX, No PSU, Steel/Aluminum/Plastic
* CORSAIR CX500 Power Supply, 500W, 24-pin ATX12V V2.3 EPS12V, 2x 6-pin PCIe, Retail
* ASUS P8H67-M LE, LGA1155, Intel® H67, DDR3-1333 16GB /2, PCIe x16, SATA 3 Gb/s /4, 6 Gb/s /2, VGA+DVI, HDMI, USB 3.0 /2, HDA, GbLAN, mATX, Retail
* INTEL Core™ i5-2500 Quad-Core 3.3GHz, HD Graphics 2000, LGA1155, 6MB L3 Cache, 32nm, 95W, EM64T EIST TB VT-d VT-x XD, Retail
* CRUCIAL 4GB (2 x 2GB) PC3-10600 DDR3 1333MHz CL9 1.5V SDRAM DIMM, Non-ECC
* XFX Radeon™ HD 6850 775MHz, 1GB GDDR5 4000MHz, PCIe x16 CrossFire, DVI /2, HDMI, DP, Retail
* SAMSUNG 1TB SpinPoint F3, SATA 3 Gb/s, 7200-RPM, 32MB Cache, Retail
* MICROSOFT Windows 7 Home Premium 64-bit Edition, OEM
This comes to $895 before shipping. I plan on reusing my DVD drive. My only real concerns here are will the power supply hold up in case I want to upgrade my video card down the road, and there are absolutely no LGA1155 mobo reviews out there yet. As far as everything else, I think it looks good.
I just built a similar system with a HD 6870. I chose a 850W PSU, so that I could easily add another later for Crossfire, cover any overclocking and additional components I may want to add in the future. Of course 850W is overkill for now, but the minimum I would chose is 650W, which will cover any future single GPU upgrade.
As others have said, that 500W PSU is not going to give you much room to upgrade. I would recommend the Corsair 650W TX PSU which will give you plenty of room to upgrade in the future. In two years there will be a new card out there in the $200 range that blows your current GPU out of the water, and you will want it. You better make sure your PSU can handle the new card or you will be kicking yourself.
Also, I know you want to keep the price under $900, but I would seriously consider moving to a P67 mobo and the K version of your CPU. You say you don't want to overclock, but for a very small increase in price you can give yourself the flexibility to do so in the future. OCing the new unlocked SB CPUs is incredibly trivial. You literally just enter the bois and change a single mulitplier value. IMO, it would be silly to pass up the ability to OC your CPU just to save a few bucks.
If you want to shave a few bucks off the price go ahead and drop down to the default case AVADirect uses. As long as you have a GPU with external exhaust that Compucase HEC case will be just fine.
The prior poster recommended the Corsair 650TX but that would be $35 more and even if I skimp on the case it'll be too much. Plus, the Centurion is a solid budget case according to nearly all reviews that I've read, plus it looks great IMO.
I do agree with the above poster concerning the K chip and P67 chipset. It's only $30 over my budget and even though I don't want to overclock now it's good to be able to easily.
I also changed my video card to the ASUS with a better cooler and slightly faster clock... and for some reason $10 less then the XFX...