Just have to put in tuppence here. I've not come across a distro that requires a minimal CPU/RAM setup, but maybe Ive just been lucky. I ran SuSE installs on p200, p233 (until the hardware died, sniff!), and currently on a p350 with no problems. (currently at SuSE 8.2/9.0). The graphical installer works fine. Also my router is running SuSE 7.3 on 12MB (!!) of ram (P130 or so cpuinfo claims), and doing fine. Ok, so thats not using X at all, but still :)
*boggle*
C.