PCI expansion slot definitions (SL390s G7)
The HP ProLiant SL390s 1U Server (half width) has one available low-profile x16 PCIe2 slot.
The HP ProLiant SL390s 2U Server (half width) has one low-profile x8 PCIe2 slot and three x16 PCIe2 slots for internal GPU support (up to 22.5W).