Thin Grey Line on Boarder of TV

Hi All - its been a while since I've posted here - i haven't needed to since Assassin was so good at getting my HTPC up and running (i'm sure everyone has seen his thread). My HTPC has been running strong for a year and a half now, but lately I have been expirencing a small problem - at the top and sides of my plasma screen (Samsung, connected via HDMI) I am getting small boarders of grey. (see picture)



The boarders will rotate (i.e. show up on the left side, then top and left side, then top and right side, then bottom and right side, etc) and are particularly annoying when I am trying to watch a movie in full screen. If I hit the 'display' button on the TV remote to change the display ratio, it will clear up but then after 30 to 120 seconds the lines will show up again.

This issue does not occur when I am watching cable (via my TVs other HDMI port). I have also tried each port on the TV and multiple HDMI cables, so I have to assume the issue is coming from the HTPC. I can give further details on the 'guts' of my computer if necessary.

I did some searching on the forums but could not find much (usually just people with aspect ratio issues or older threads about HD/non-HD). Anyone have any ideas??

Any help is greatly appreciated. Thanks again to everyone that makes this board so great.

Thanks for the replies!

Tiddles88 - I'm not exactly sure where to check via the graphics control panel (and my googling of Catalyst Control Centre didnt turn up anything that seemed to be related to my system, but if you have more information i'll be sure to check it out). I did ensure the TV and computer were both set at 1080p/60hz.

Andrew - I had the input HDMI 2 "name" set to PC, but i assumed that was just a description. The HDMI2 is labled HDMI/DVI, so I moved the cable box to that one and the HDMI1 to my HTPC (and changed the description to PC). I have not seen an option for "no overscan" on the TV.

HOWEVER, changing the HDMI port seems to be working so far. I have also noticed that utilizing the HDMI 1 port (i.e. the NON-HDMI/DVI port) has enabled me more options with my picture. so maybe that was the issue all along? Ive een on the computer for about 15 minutes and have not seen any issues...

I'm not really sure why Samsung has labeled the second input that way - its definitely an HDMI port (not a DVI port) but the fact that it has less picture options is weird to me ...

Assassin - thanks for the replay, but when I ran the hotfix, it said it was not necessary for my computer.

Thanks again for the help.