powerstrip and rolling pc monitor on arcade setting?

[Xphile]

umm...was just playing around with the settings in powerstrip on my mame computer hooked up to a mitsubishi diamond scan 17 FS monitor on an nVidia geforce 2mx, and noticed 640x 480 arcade mode 15-ish kh..

selected it, confirmed it and poof...my screen started rolling uncontrollably, with brief flashes of desktop showing a blue sky win98 backgroud and REALLY LARGE TEXT (compared to my normal 800x600 sized text) in whatever confirmation box is on screen  ...the front LEDs of the monitor are also blinking the same way they do when the computer is off with the monitor left on...

So, the screen rolls, the LEDS blink, and I get a brief glimpse of the desktop, the the LEDS blink off again, the screen rolls again, and on and on every 1 second or so (as it tries to come into sync I guess)

is this a good thing for my arcade monitor?  does this mean my video output is so low  (maybe even 15khz:-)  that my computer monitor doesn't think it's supposed to be displaying it?  when I hack it into my standard resolution arcade monitor's R,G,B, sync,and ground do you think it will work?

I guess the only way to know for sure is to try it, but I thought I'd ask first,  just in case someone recognizes these symptoms as being arcade monitor syncs being driven into a PC monitor or not..

have a great nite,

[generousben]

i still dont get how anyone can get  a decent 640x480 picture on a 15k.

640x480 needs to be interlaced which can be a bit ---steaming pile of meadow muffin---.

when i run my pc monitor in windows at 15k it just turns off.

if you  card supports custom resolutions  
then you can easly drive an arcade monitor at 15k uninterlaced with partial desktop support.
any radeon card will drive a 15khz monitor(not sure about geforce)