Azaelus:
Don't know if your new rig came with WinXP, but I've been running a P4 for some time now, with WinXP, and here are a few notes:
You'll get the occasional freeze when you move a unit to the very top or bottom row of tiles. (not the turn you move it there, but the turn you want to move it away). the workaround is to have the "automatically save each turn" activated, and just load the last year's turn - then switch that rogue unit to "automatic' - the AI moves it quite happily away from the troubled tile.
And welcome back to the interceptor scramble bug. Disabling the wheelmouse in regular formats worked, but for some reason it's back again with the XP and P4 combo
With the P4 power you can experiment with some hairy custom-sized maps (try a 512 x 512 - and settle back for a week's play!!) as the processing power can handle the load quite well. - and if you want a slightly different experience, set a humungous map to 90% water and download and play aquatic versions of the smac and smax factions - get them
here
G.