For 6016GT-TF server, do I need to buy an additional riser card if I use 2 graphics cards (1 x capture card - Nvidia Quadro FX3800/4800 (full length, full size) and 1 display card (half-length) and 1 10G LAN card? If yes, what is the part number?
No need to buy extra riser card. Those come with the server are enough.
RSC-R1UG-E16R ---> right side, for Graphics Card A (PCI-e x16)
RSC-R1UG-E16 ---> left side, for Graphics Card B (PCI-e x16)
RSC-R1UG-UR ----> middle, for 10G LAN card (PCI-e x8)