This page covers G3 upgrades that fit in the Level 2 cache socket of the Power Macintosh 4400, 5400, 5500, 6400, 6500, 7220; Performa 54xx, 6360, and 64xx; Twentieth Anniversary Mac; StarMax 3000, 4000; Power Computing PowerBase; Umax SuperMac C500, and C600. Check with the manufacturer of the upgrade to see which models are compatible.