Not a problem.
First of all, Powerstrip can be downloaded for free from
http://www.entechtaiwan.com/ It can be registered for a price, but at this time, I am unaware of what benefits you gain from doing so. So far the unregistered version has done everything I have ever needed it to.
My experience with this program is limited to my setup, which is a Radeon 9600 Pro, the ATI Component adapter (DVI port), and my Panasonic CT-34WX50 HDTV. And I am not currently at that computer, so I couldn't even paste the settings I have if I wanted to. But what I found is this: you can go online and search for the particular timing paramters that pertain to your particular tv, but if you have the patience and the technical understand, I found it was best to ignore them and start from scratch on my own.
What happens is this. ATI cards are programmed to use the 480p mode by default for any XXX by 480 resolution. However, every HDTV that I have seen that is capable of 480p display, is capable of 1080i display as well. These are common HDTV broadcast signals, as well as the newer 720p format. Now, if your TV is capable of 1080i, your TV is also capable of 540p. You might not have heard or thought of 540p because nothing I know of uses this signal, but never the less, your TV can do it. Instead of displaying 1080 lines 30 times every second, (doing 540 in one 60th of a second, and the other 540 in the other 60th) it displays 540 lines 60 times every second. It's the same thing, it's just that nothing uses that format. (Vice versly, because your TV can do 480p, your TV can also do 960i, another unsed signal. And if you have a 720p capable HDTV, you have 1440i as well.)
Now I've rambled on a bit about that, and most of it is useless information to everyone except for HTPC users. Let's say you had a general run of the mill transcoder (therefore, not ATI's adapter). You could use this information to construct any resolution that would fit best in which ever given signal. For example, 640 x 480 in 540p. 800 x 600 in 720p. 1024 x 768 in 960i. 1280 x 960 in 1080i. And so forth.
However, if you are using an ATI adapter like I am, I regret to say that you are limited to exactly 5 desktop sizes that will not result in a virtual desktop. This is a very poor decision in my opinion, and while there may be some technical excuse for it, it is one that I hope ATI remedies soon.
Anyway, the point of all of this is that because of the inherent underscan and overscan in television sets, whatever your vertical resolution is set to, you need a mode that is greater than that resolution. 640 x 480 won't fit properly in 480p, but it does fit wonderfully in 540p. And Powerstrip is the program that lets you do that.
Powerstrip is a program that talks directly to your video hardware and tells it exactly how to send the signal that your computer generates to the monitor (or HDTV). This give you complete control over the refresh rate as well as a slew of other features of your video signal. One of those features is referred to in Powerstrip as the front and back porch. The front porch controls the number of scan lines to wait until drawing the desktop would be visible (i.e. not off the top of the screen). The back portch controls the number of scan lines to hold off from drawing the bottom of the desktop (i.e. defining the bottom of the visible screen). Properly setting the front and back porch will result in a perfectly fitted desktop on your TV screen.
Now, if only it were as simple as setting those numbers. Unfortunately it's a little more complicated than that, but not by much. Before you start Powerstrip, I would recommend you read any of the number of poor to well written tutorials on using Powerstip that can be found on the net. They do a much better job at explaining the necessary steps than I ever could. Notably, read:
http://www.ramelectronics.net/html/powerstrip.htmlhttp://www.keohi.com/keohihdtv/experttips/markrehjon/htpc_superguide.htmlhttp://www.avsforum.com/avs-vb/showthread.php?s=&threadid=206854The last link in particular will contain actualy values that you could theoretically use if your TV matched the exact specifications as the TV that that forum poster has. Chances are, that won't be the case and you will be left, as I was, on your own to figure out the right timing.
This requires a great deal of patience, and having a monitor attached to your video card at the same time is a HUGE plus. What you're going to do is start with a base resolution such as 640 x 480 @ 60Hz in 480p. Get it working on your monitor (should be easy) and get it working on your TV (should be a little tricky, but not too hard). Once you have your monitor and TV agreeing on the numbers and you see a good picture on your TV, you've gotten through step 1. It does not matter how crappy Powerstrip makes your monitor picture look (squashed, stretched, WAY off center) as long as it's legible. Now you need to start changing the numbers in Powerstrip, to switch the resolution to 540p. The links provided above give you a good baseline to start from. The vertical refresh rate should stay exactly the same, and you should note what it was in 480p mode so that you know if you deviate too far from it, you can set it back and fix it. Incorrect refresh rates will result in an unviewable picture with lots of scrolling, and if the refresh rates are way too off, you could potentially damage your TV. Hence all the "do this at your own risk" warnings in almost every guide you come across. Once you have a viewable picture for 640 x 480 @ 60Hz in 540p, you are well on your way to becoming a Powerstrip master, and you ready to try for some more "crazy" custom resolutions.
Note however, like I said earlier, that if you are using the ATI Component adapter, you are limited to exaclt 5 resolutions that will not result in a virtual desktop. They are 640x480, 720x480, 856x480, 1772x1000, and 1920x1080. You can use Powerstrip to get the first three resolutions in 540p with no overscan. The last two will run automatically in 1080i, but you can use Powerstrip to tweak them. It is possible with Powerstrip to have no overscan in 1772x1000, but it is physically impossible to prevent overscan in 1920x1080.
OK I better cut this here, I don't know if half of this information was really useful to you all, but I hope it cleared up a few questions. Please feel free to ask if you need me to clarify any points.
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