You can use the following graphics adapter which are tested on this unit.:
NVIDIA Quadro4 100NVS AGP (64MB, dual VGA) full height
NVIDIA Quadro4 100NVS AGP (64MB, dual VGA) low profile
NVIDIA Quadro4 100NVS PCI (64MB, VGA & DVI)
NVIDIA Quadro4 200NVS (64MB Dual VGA) full height
NVIDIA Quadro4 200NVS (64MB Dual VGA) low profile
DVI cable harness for NVIDIA Quadro4 100NVS
NVIDIA Quadro4 400NVS (quad head)
NVIDIA GeForce4 MX440/8 (64MB, 8XAGP, VGA,S-video) full height
NVIDIA GeForce4 MX440/8
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