7950 - no signal via HDMI until Windows boot

[foxrocks]

I've got an MSI Twin Frozr 7950. When connected to my Panasonic TV via HDMI, I get no image until Windows has loaded. Obviously this makes it impossible to do anything in the BIOS, and if I want to do that I have to try and borrow a monitor and do it via DVI, which is annoying!

Has anyone else had this issue? What could be causing it?

I've also tested it with an MSI 7870 and had the same problem. However my previous card, an MSI GTX 560 Ti, was fine. So it seems to be an AMD thing.

edit: oh yeah, it also doesn't work if I hook the TV up to the motherboard's HDMI and use the IGP

 

[foxrocks]

That could be it, except it wouldn't really explain why the 560 Ti worked absolutely fine.

 

[foxrocks]

Ok cheers guys, I'll look at the scaling settings on the TV as I've never tinkered with them before.