Just Curious if this setup is decent

Hi, been reading about Bitcoin for years but Ive never been able to mine and I think I finally have a decent setup and wanted to confirm this with you guys. Here are my specs:

AMD Athlon II x4 630 2.8GHz
32GB DDR3 1600Mhz RAM
Radeon HD 6850 x2
MSI 970A-G43 AM3+ AMD 970 SATA 6Gb/s USB 3.0 ATX AMD Motherboard
Thermaltake SMART Series SP-750PCBUS 750W ATX 12V 2.3 SLI Ready CrossFire Ready 80 PLUS BRONZE Certified Active PFC Power Supply

Ive been running this system for 12 hours on BTC Guild using cgminer and have been at a steady 0.5Gh/s and both of my cards are underclocked.
Soon Ill have 3 ASIC block erupters @333mh/s each that I will run combined with the Radeons. Which will give me about 1.5Gh/s in total. Is this a good setup or is there more information needed?