I want a new PC. Only using the display from the old one.
I think I am going to OC and in that case want the "Opteron 165"
I have never OC before, and dont know what RAM and MOBO to buy.
I would recommend a DFI LanParty nF4 (or Xpress 3200 if you want ATI) or an ASUS A8N-SLI Deluxe or Beyond (A8N32-SLI Deluxe, A8N-SLI Deluxe or A8N-SLI Premium), or the EPoX EP-9NPA+Ultra, as those are the best overclockers for Socket 939. Memory wise: I would pickup some OCZ Platinum Series memory, as those are the best overclockers RAM. You could also grab some Corsair XMS or Crucial Ballistix/Tracers, though Corsair XMS doesn't overclock as well as OCZ or Crucial, it is often cheaper.
I am pretty much one step a ahead of you. Got the Opty 165 and Asus A8R32 MVP deluxe a month or so ago and ran into OCing problems with my value ram, so I just got 2x 1 gig sticks of dual channel OCZ platinum ddr500. Got em in last night but don't plan to begin the OCing till Sunday or Monday.
Or what is this ?
OCZ 2048MB Dual Channel Platinum Edition
If I OC a 165 from 1.8 -> ~2.4 is the PC3200 ok memory?
When would one want the PC4000 ?
The PC3200 will overclock to 260MHz most likely, and will be cheaper than the PC4000. 267MHz FSB will give you your 2.4GHz, and that RAM should be able to reach 267MHz, but you'll have to relax timings to 3-3-2-8 or 3-3-3-8 probably.