Infini-D
As a fellow HTPC & EH8500 owner, i may be able to help you out here.
This might get a bit complicated, so bear with me. I'll try to not get into too much detail.
BTW - Most of this is observed, i'm not an engineer.
There are many variables in this whole process.
Imagine the signal that's being sent to the projector as a large rectangle that contains the video. Your projector projects part of this rectangle, depending on the settings in your projector. With your projector's Phase settings for example, you can shift this large rectangle around some.
Then on top of that, your PC's desktop is inside this large rectangle, usually as a smaller rectangle than the large rectangle; at the left, right, top and bottom, there's some "black". The amount of this black can vary. You can use a tool such as PowerStrip to precisely control the amount of this 'black' around your PC's desktop. (Basically you'd use PowerStrip to shift your desktop around inside that larger rectangle. You can also use PowerStrip to decrease / increase those black areas, thereby shrinking / expanding the size of your desktop picture inside the large rectangle (this does NOT affect the resolution of your desktop btw. But that's a whole different and very technical discussion that we don't need to get into here.))
So what you're experiencing can be any combination of these variables coming into play. What i'd do:
1 - Go into your projector's Phase settings, and set both Horizonal and Vertical phase to 50.
2 - If you have PowerStrip (highly recommended for CRT projectors):
a - Go into PowerStrip, and go into the Advanced Timings of your resolution settings.
b - Use the arrows in the top left area of the PowerStrip window to move and expand / shrink your desktop until it fits on your screen as close to perfect as possible. BEWARE: expanding horizontally will change the frequency (one of the input boxes on the right, in the middle). I normally go back and forth between the two: expand and shift the desktop some, then re-adjust the frequency back to where i want it (71.928 in my case), and then expand / shift again with the arrows, etc.
3 - Fine tune with the projector's Size and Phase controls.
Hope that helps.
G
Oh, and PS: You may want to modify you sig on this forum - right now it contains a long list of your equipment, which 1) is against the rules and 2) makes your sig longer than your post's actual content.