System Board Option # Manufacturing Part # Description Previous Part # n/a 375-3463 [F] Motherboard w/ 2 × US IIIi 1.5GHz, 0MB n/a ?371-0820 ?CPU Heatsink, n/a ?371-2609 ?CPU Heatsink n/a ?375-3462 ?0MB Motherboard, L n/a n/a 375-3464 [F] Motherboard w/ 1 × US IIIi 1.5GHz, 0MB n/a ?371-0820 ?CPU Heatsink, n/a ?371-2609 ?CPU Heatsink n/a ?375-3462 ?0MB Motherboard, L