I have an Optiplex 745 and I went with a ATI Theater Pro 550 PCI card low profile card
for $20 with shipping
I use it with a Comcast Digital Adapter and use Cyberlink Power Director for viewing/recording
with that said I would go with a Hauppage model WinTV model
since getting software for the ATI was difficult
this is on Newegg
http://www.newegg.com/Product/Prod [...] vtunercard
I have also used Hauppage WinTV USB and pci cards
and the WinTV 2000 software that is included is easy to use and works well
alot of those cards are PCIe express x 1
so make sure what slots you have available
depends on the form factor of the 755
for example the Mini Tower will have more slots than the SFF or Slim Desktop
if you can give me the model of the 755 (MiniTower,Desktop or SFF)
I can look it up
also if you can give me preferred shopping sites (ie Newegg,Ebay)
I can help you look