A quality 300W PSU would do that job. You can check AMD's recommended PSU list on their website. As far as PC133 vs DDR, a standard stick of DDR2100 (DDR266) would have twice the memory bandwidth of that of a stick of PC133. So yes, get DDR.
Athlon XP 1600+ @ 1800+
Alpha PAL6035 w/ 40cfm YS Tech
Shuttle AK31 v3.1
256MB OCZ DDR300 CL2
VisionTek GF 256 SDR
40GB WD 7200RPM ATA100
8.4GB Maxtor 5400RPM ATA33
Athlon 64 3000+ Winchester @ 3800+ (2.4Ghz/1.45V) Soltek SL-K8TPro-939 / Arctic Cooling Freezer 64 Pro Mushkin Black L2 V2 TCCD 512MBx2 @ 440Mhz (2-3-3-6)
ATI X850 Pro (572/1226) / Zalman VF700-Cu
40GB WD 7200rpm 2mb / 300GB Seagate 7200rpm 8mb Creative Audigy 2 ZS / Logitech Z-5500 Westinghouse LVM-37W1 37" 1080p LCD
Research show that 71% of women would like men who have better MEMORY, the other 29% say they prefere men with more RAM.