The Asus P5A is a Super 7 mainboard. It can handle Pentium133 through P200's, Cyrix, and AMD K6 and K6-2 processors. It may be able to use Pentium 233 MMX's and K6-3's. This is a Socket 7 form factor mainboard. Super 7 denotes 100 Mhz FSB capability.
Durons and Thunderbirds need a Socket A mobo. Super 7 is long in the tooth. If the P5A can run K6-3's, this gives you 90% of the performance of PIII's, Clock for Clock.