Well first of all, I would highly recommend you steer clear of the OCZ sets. On my rig (not in sig currently), I run the ASUS A8N32-SLI Deluxe motherboard with OCZ Platinum DDR500 2x1GB....and I can't even get them to run stock timings at 200MHz...or even POST at 250MHz (DDR500, stock). I'd go for the cheap GSkill 2x1GB kit (red heatspreaders). Much better bang per buck there. You have dividers for a reason, use them
Go for the XFX GPU. An 8800GTS 512MB WILL NOT be bottlenecked (too badly) by your CPU. I know, I have the same setup (with an Opteron 165 @ 2.8GHz). Brands to buy for Nvidia GPUs:
XFX, eVGA, BFG.....end of story. All have great warranties. So pick between those three.