CPU
1.Pentium 4 is single core processor, of course ur friend's amd dual-core processor faster than urs one.
2. Amd dual-core consume 65Watts, compared to urs P4 processor which uses 80w above if not mistaken
3. For my opinion, intel Core 2 Duo E6000 series or (E8000 series or Quad series if u got high budget). Besides that, i feel that Intel product more reliable than AMD...
For more CPU benchmark details:
Here
GPU
Competitor of Graphic card X1650 is Geforce 7 series GPU. If really want to compare ur GPU, Geforce 4 series... totally outdated...
2. If you are geforce supporter, try 8800GS (If not mistaken, nvidia currently stopped reproduce it, and retailers priced down it... ) low price with high performance GPU. Best choice!!
3. Radeon HD 3000 series (consume less wattage)
(low budget 3450, 3650)
(high budget 3850, 3870, 3870X2)
Note: All above just my personal opinions, I'm more concern power consumption rather than CPU and GPU speed.....
Link:
8800 vs 3850/3870