HP 500B - Manual (Page 21)

Expansion Cards
The computer has one PCI expansion slot, two PCI Express x1 expansion slots, and one PCI
Express x16 expansion slot. The expansion slots accommodate full-height or half-height expansion
cards.
Figure 2-10 Expansion Slot Locations — 500B/510B
Figure 2-11 Expansion Slot Locations — 505B/515B
Table 2-2 Expansion Slot Locations
Item Description
1 PCI Express x16 expansion slot
Expansion Cards 13