Dell OptiPlex 990 (Early 2011) - Manual (Page 87)

External Connectors
NOTE: Available video connectors may
vary based on the graphics card
selected.
System Board Connectors
PCI 2.3 data width (maximum) — 32 bits
Mini-Tower, Desktop one 120-pin connector
Small Form Factor, Ultra
Small Form Factor none
PCI Express x1 data width (maximum) —
one PCI Express lane
Mini-Tower, Desktop one 36-pin connector
Small Form Factor, Ultra
Small Form Factor none
PCI Express x16 (wired as x4) data width (maximum) — four PCI Express lanes
Mini-Tower, Desktop,
Small Form Factor one 164-pin connector
Ultra Small Form Factor none
PCI Express x16 data width (maximum) —
16 PCI Express lanes
Mini-Tower, Desktop,
Small Form Factor one 164-pin connector
Ultra Small Form Factor none
Mini PCI Express data width (maximum) —
one PCI Express lane and one USB
interface
Mini-Tower, Desktop,
Small Form Factor none
Ultra Small Form Factor one 52-pin connector
Serial ATA
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