Image not in place with different resolutions

[ShavedAlpaca]

I was going to start recording gameplays, post them on youtube and so on. Because youtubes hd is 1280x720 resolution I thought I would change PRs resolution to that. When I do the picture moves to the left by about an eight of the screen width. I normaly run it on max 1920x1080 and its fine and bang in the middle and this would also increase the framerate of the game while recording.
What am I doing wrong or do I have to change to make it work properly?

[Mad-Mike]

Youtube HD is 720 OR 1080

Just stick to your normal rez, then what ever program you use to edit the vid. Renderer it as HD.

[ShavedAlpaca]

kthxbai