@kryptykal,
This is a fun transition board, but do not expect to overclock any of the PT880 boards very much. Rarely do people get more than 300MHz FSB. Best volt modding guide for this board on
VR-Zone still only achieves moderate results.
With such a low rate of return on OC efforts, the best thing to do with this board to get solid everyday performance is to install a 1066 CPU with a high multiplier, such as the new E7600.
Keep in mind any CPU not listed on the compatibility list on the Asrock site will require you to have access to a CPU that *is* on the list in order to flash the BIOS to support the newer CPU. Check a few posts above in this thread for a link to an unofficial, but excellent quality, BIOS that supports more things than Asrock's.
You may also need an older AGP card at first, too (check Asrock to see which BIOS update supported the 3850, and you'll need another AGP card if the board as purchased has a lower BIOS version).
As for RAM, the board you upgrade to after this one is likely to require DDR3, so getting "super" DDR2 and thinking of using it in the future is now a bad idea. Since you are unlikely to exceed 333MHz FSB, get DDR2 at 667MHz that has tight timings and is rated for 1.8v for best performance (setting it later to 266/533 in the BIOS actually seems to work better).
Doubt you'll need more than a 550W PSU; I'm partial to Corsair in that range.