A question about XRGB and LCD monitors

Started by sigmaris, November 03, 2003, 09:04:28 AM

Previous topic - Next topic


I have a question about the XRGB2+ that i posted on the old boards just before they were closed :( and so i didnt get any answer to it. I'm posting it again on the new boards in the hope that someone might see it. I was thinking of getting an XRGB to play my consoles on a vga monitor, because the CM8833 Amiga monitor I use is getting old and I don't want to be stuck without an RGB monitor if it breaks. However I have some questions about the XRGB before I buy one. The firs question is, if say my PS2 is outputting an interlaced 480-line picture that displays on my rgb monitor, how will it look on the VGA monitor? I know that an interlaced display only draws half the picture lines at a time, and I also know that a 15kHz non-interlaced 200-line signal will need to have the lines doubled to work on a VGA monitor. The thing is, since an interlaced 480-line signal is only drawing 240 lines at once, do these lines get doubled so that the VGA monitor shows all the even lines doubled one frame, then all the odd lines doubled the next frame (which would look sorta wobbly)? Or does it put the odd and even lines together to make a full 480-line non-interlaced image? Or else does it keep the interlacing and make the VGA display interlaced? Sorry if it sounds complicated, but I'm just worried that if I get an XRGB it'll display interlaced stuff with weird lines all over it or something.

Also, I heard that it's common for LCD monitors nowadays to support video input from games consoles (e.g. they support 15kHz as well as VGA 31kHz). Is this true? For example I found a monitor here: http://www.maplin.co.uk/default.asp?CartID...getmodule=36335
now it says Inputs: RGB Analogue and 15pin D sub, i wonder does this mean it has an rgb input as well as VGA input? Has anyone else heard of LCD monitors that support RGB (maybe the ones with builtin tv tuners?)

anyway, i hope someone can help if u can b bothered reading thru all of the text :D


Quoteall the even lines doubled one frame, then all the odd lines doubled the next frame (which would look sorta wobbly)?
This doesn't look as wobbly as you'd suggest and in fact looks quite nice.  The XRGB2 has a 'scanline' mode which essentially works like an interlaced display, leaving every 2nd line dark so the blending works better.  In practice I don't notice much difference between this mode and non-scanline mode when presenting an interlaced signal.

The simple bottom line is: if you have an XRGB2 and some RGB cables for your consoles you'll be getting the very best image quality around.  That's it, really - the XRGB is amazing, and you won't be disappointed.

As for your LCD monitor question, all monitors are different, and there's no guarantee 15kHz support + VGA support means 15kHz RGB support.  While it would be trivially easy to implement this in a monitor you just know the manufacturers hate you and would like to shove rocks up your ass rather than give you a product you'll enjoy.  Also, make sure the seller has a great return policy, or will let you drag a console into the shop for testing before you buy it.



Thanks for clearing that up, i guess the wobbles are too fast too see :)
One last question though, if the XRGB gets a 50hz (rgb) input from the console, does it output vga with a 50Hz refresh rate, or does it only work with 60hz games? My monitor can do 50Hz, so i'm not worried about refresh rates being too low.


As a friend of mine found the hard way, 50Hz does not get adjusted to any other frequency.  Caused havoc with his LCD and his Raiden Fighters PCB, which runs at ~54Hz or something silly.


great, thanks for the info again. I'll probably be getting an xrgb soon then :)