I'm getting a new PC. I decided on an AMD Phenom II X2 550 for CPU and HD 4850 512 MB for GPU. Please suggest an AM2+ motherboard. I don't plan to go X-fire and won't be doing much overclocking. It should support two IDE/PATA drives. My budget is $100. Will 4 GB 800MHz DDR2 be enough? I read in ASUS's website that Windows XP does not recognize more than 3GB RAM. Is it right?