Gigabyte’s P55A-UD4P cuts costs by using the processor’s PCIe 2.0 connections to host its high-bandwidth controllers. Two of the primary graphics card’s 16 PCIe lanes supply its USB 3.0 and SATA 6.0 Gb/s controllers, and Gigabyte disables six more lanes to make the upper slot an effective x8 interface. The USB 3.0 and SATA 6.0 Gb/s controllers revert to the chipset’s 2.5 GT/s lanes whenever two graphics cards are installed, to preserve the x8 transfers each graphics card needs for optimal CrossFire or SLI performance.
Thus, users with a single graphics card must sacrifice half of its peak bandwidth to enable 5.0 Gb transfers to the USB 3.0 and SATA 6.0 Gb/s controllers, while those with two cards must live with 2.5 Gb/s bandwidth limits on USB 3.0 and SATA 6.0 Gb/s controllers. Neither of these sacrifices is huge or even noticeable on most of today’s hardware, yet anyone trying to future-proof their system could be left cold.
Hard Drives - Check out the performance charts and pick whatever 500 GB per platter drive performs best under your usage patterns. The 2 TB WD Black and XT from Seagate are good choice but at smaller capacities, you are limited to the Seagate 7200.12 or the Spinpoint F3. The 7200.12 excels in gaming, multimedia and pictures whereas the F3 wins at music and movie maker. See the comparisons here (copy past link in manually, link won't work in forum):
Look at the tests that reflect your usage and choose accordingly.
Case - The Antec Illusion is the Antec 300 w/ fans already installed....same price on newegg ....however, this is a small case....you may notice this by the allowable combos that newegg has giving you only the 380 and 430 watters as choices on PSU's in their combos.
I have to agree.....if you are gonna stick w/ a single GFX card, the Six Hundred Case and the EA-500 combo is appropriate giving both proper cooling, volume and power for an OC's CPU and single GFX card. If you might go w/ a 2nd GPU. I'd move up to the Nine Hundred or 902.