Are you saying you only use onboard (Intel) video now?
According to the manual, the Small Form Factor 780 can take one PCI-e X16 card, BUT it must be a "low profile" card. Don't know the HD 6450 card, but unless it's low profile, it won't fit...
NOTE: The PCI Express x16 slot is disabled when a display is connected to the integrated video connector. So be sure to connect the monitor to the add-in PCI-e video card after it's installed.
Forum Member since 2004
I'm not a Dell employee
Not all the sapphire models physically fit. Thats why ASUS EAH6450 SILENT card is recommended.
Must be low profile AND only 1 slot wide.