So I just put the Giga Designs upgrade in my MDD whose CPU died a while back. The motherboard was checked out and is OK. However, when I power it up I get the startup chime but no video. I read that resetting the pram can help so when I try it never chimes again. I've tried plugging the keyboard into the USB ports on the computer as well as my monitor to no avail. Not sure what to do and I need to get this fixed very soon. Any help would be greatly appreciated. I've tried reseating the video card and I also pulled an old PCI video card from another computer to test and it didn't work either.