Dell OptiPlex 790 (Early 2011) - Manual (Page 85)

Cards
PCI
Mini-Tower up to one full-height card
Desktop up to one low-profile card
Small Form Factor none
Ultra Small Form Factor none
PCI Express x16 (with support for PCI-Express x1)
Mini-Tower up to one full-height cards
Desktop up to one low-profile cards
Small Form Factor up to one low-profile cards
Ultra Small Form Factor none
Mini PCI Express
Mini-Tower none
Desktop none
Small Form Factor none
Ultra Small Form Factor up to one half-height card
Drives
Externally Accessible:
5.25–inch drive bays
Mini-Tower two
Desktop one
Small Form Factor one slim line bay
Ultra Small Form Factor one slim line bay
Internally Accessible:
3.5–inch SATA drive bays
Mini-Tower two
Desktop one
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