i am getting new motherboard, memory, processor and case the rest is from my old gateway i up graded until now. and i am wondering how many watts i will need on the power supply. the specs are as follows: AMD Athlon XP 2500+ Epox 8RDA3G GeForce FX 5200 SB Audigy. 512MB DDR 3200 40 GB HD DVD Drive CD RW Drive Floppy Drive and 3 80 mm case fans do you think 350 watts will be enough? because thats what comes with the case. and the case is only $22. and also when i install my new motherboard will i have to wipe my hard drive clean first? i know its like a whole new computer but i am just making sure.