Well, I just had a bit of a play with an ATom Intel 945 based Fujistu Microbook. It wasn't pleasant to be honest - but mainly because of the unit itself and the Intel drivers. I created a custom15khz.txt and removed every res I saw in the wiki page except for 640x480, 800x600 and 1024x768. Still, in quickres, there were a bunch of other resolutions I couldn't remove. I also tried generating a modeline for 30i, and was able to access it in the multires selection meu - but the system locked each time I tried it!
'Modeline "640x480@30i" 5.49 640 672 688 720 480 491 493 404 interlace'
I used an online Xfree86 Modeline generation website to make this....
(1) Of course, the system has a built-in screen so I had to use the VGA Port
(2) The system only displays access to the VGA port settings when something is connected. Of course, with a simple NTSC RGB screen there is nothing but connections to RGB -which makes the system think nothing is connected! I will research to see what else I have to do at the vga pins to have the system recognise something is connected.
(3) Quickres does not let me change the res of Display #2. I had to use Multires for that.
With the VGA as the 2nd screen, I received a few 'Out or range 15.7kHz, 50Hz' messages, which makes me think it must have been 800x600 or 1024x768 - even though I was sure I was setting 640x480. Certainly Multires was reporting 640x480. I couldn't confirm the operation of Interlacing at all - there is just no way to tell. In a later attempt with Powerstrip installed, Powerstrip was not reporting that interlaced was running, but since powerstip can't change interlaced settings on Intel IGP, I suspect it can't read them either.
I tried the vga port as the primary port, and when I applied my settings I remote-controlled the system via WinVNC. The screen, however, reported an 'Out of range 20kHz'. So on a bit of a whim I installed Powerstrip, and it too was reporting a 20kHz signal.
So in all this I couldn't confirm if the VGA port was outputting the right values or not, and non conclusive as to whether I should continue. But I've not given up....
Lukeyson