Cable Modem causing video screw up

[barlav]

I'm troubleshooting a pc problem. When cable modem is connected to NIC in the video is screwed up. It scrolls the screen. The video starts in the middle of the screen and then wraps such that the right part of the picture shows on the left part of the screen. This problem occurs using power dvd, quick time and media player. I've narrowed the problem to the Cable modem. When the modem is unhooked from the system and the system is restarted all video works fine. Once it's plugged back in the problem reoccurs. Anyone ever see this or know how to resolve? Tried several NIC's, Monitors and Video Cards all with the same result. Perhaps it's a bad Cable modem?

Thanks for any input.

 

[Muadib]

Sounds like an IRQ conflict with the NIC, and vid card to me. I would check that first.

 

[barlav]

Thanks. Tried that. NIC was built into mobo. Disabled that and then installed PCI NIC, same problem. Tried it in all pci slots with same result and checked IRQ's and there were no conflicts. Any other thoughts?

 

[Muadib]

What operating system are you using?