Dell OptiPlex 990 (Early 2011) - Manual (Page 94)

Memory
Desktop, Mini-Tower, Small Form
Factor 16 GB
Ultra Small Form Factor 8 GB
Video
Integrated
• Intel HD Graphics (with Intel
Celeron/Pentium-class CPU-GPU
combo)
• Intel HD Graphics 2000 (with Intel
Core i3 DC 65 W and Intel Core
i5/i7 QC vPRO 95 W-class CPU-
GPU combo)
Discrete PCI Express x16 graphics adapter
Audio
Integrated four Channel High Definition Audio
Network
Integrated Intel 82579LM Ethernet capable of
10/100/1000 Mb/s communication
System Information
System Chipset Intel 6 Series Express Chipset
DMA Channels two 82C37 DMA controllers with seven
independently programmable channels
Interrupt Levels Integrated I/O APIC capability with 24
interrupts
BIOS Chip (NVRAM) 80 MB (10 MB)
Expansion Bus
Bus Type PCI 2.3, PCI Express 2.0, SATA 3.0 and 2.0,
USB 2.0
Bus Speed: PCI Express:
94