Build Upgrade, Critique Wanted

Thoughts on this build/upgrade? I've already got some parts, and I'm looking to spend as little as possible.

Things I want/need: 2-way SLI (3-way is too much), Z68 chip, unlocked CPU, (semi-) modular PSU

Case: Coolermaster Centurion 5 $50 (already have)

CPU: Intel Core i5-2500K 3.3GHz $225

Fans:
- 2 x Enermax Magma UC-MA12 120mm (one for case, one for CPU) $24
- 1 x Gelid Solutions FN-PX08-20 80mm $9
- Zalman CNPS10X Performa 120mm CPU Cooler $50

HDD: 500GB Hitachi 7200RPM SATA II $50 (already have)

SSD: Kingston SSDNow S100 16gb SATA II $60 (for Smart Response SSD caching)

RAM: 2x2gb PNY XLR8 1600MHz DDR3 8-8-8-24 $50

Motherboard: Gigabyte GA-168X-UD3-B3 SATA III USB 3.0 2-way SLI x16 x8 Smart Response SSD $160

PSU: Raidmax Hybrid 2 RX-530SS 530 watt SLI/XFire Ready Modular LED $55

GPU: EVGA GTX460 768mb @ 907/1814/2133 $140 (already have)

Sound: ASUS Xonar DS 7.1 24-bit 192KHz PCI $50 (already have)
________________________________________________

Total: $923
- $290
______________
$633


I don't want to replace anything that I already have... I'm 16 and on a tight budget. The main upgrade is changing out the AMD DDR2 / Phenom II X2 555 stuff that I have in right now.

The first step of the upgrade is upgrading the RAM, CPU and Mobo ($435).

Thanks for any feedback!