Mortal Kombat doesn't sync - is it the ArcadeVGA or Arcade Monitor?

[Anubis_au]

Hi guys

I've posting this up as I am hoping to get some help resolving an issue.

I'm testing games on my setup, and Mortal Kombat did not syncronise... I got a rolling picture on the screen instead.

Now, here's the problem:

The webpage on the arcade monitor says it can sync to any vertical frequency between 48 and 65Hz.

http://www.highway.net.au/parts/monitor_&_chassis/4808.html

Mortal Kombat's 53Hz is well within that range.

The arcadeVGA website says it has a special mode timed at 53Hz for Mortal Kombat.

http://www.ultimarc.com/avgainf.html

And yet, Mortal Kombat is NOT syncing.

The question I'm putting out there for the community, is what test(s) should I do to determine if its the card driver or the monitor itself that is the culprit here.

Any help would be appreciated.

Cheers,
Anubis.

[Zebidee]

They didn't say any - they said "V-Frequency:48~65Hz" , which can really mean a lot of things.  Mostlly it means that it is optimised for 50hz & 60hz modes.  But ones in the middle, ie closer to 55 often are often out of range.

That Mortal Kombat res on avga cards won't work for most of my arcade monitors, but works well on my Sony broadcast monitors.

[AndyWarne]

Most of the ArcadeVGA resoluations are 60Hz vertical, but some, which have a large number of lines such as 640 X 288 are 50Hz. So if the monitor syncs to these 50Hz and syncs to the 60Hz ones but not to the 53Hz thats very strange!
Is only the one resolution affected?
Andy

[Anubis_au]

I've seen the monitor struggle (ie not work) with games that are designed for 25Hz displays. Pretty much every CGA-res game I've tried (1942, pacman, bombjack, SF2, wonderboy) all worked.

I just rang the monitor vendor. They suggested that Mortal Kombat has a setting on the board to select between high, med and low res and maybe this is why I couldn't sync... sounds like BS to me but I thought I'd put the question out there... is there merit to their claim about a res switch? Some seting to flag in MAME?

[ahofle]

This may be a silly question, but have you tried adjusting the VHold pot?  How badly is it rolling?  Also I assume you are using the 401x256 AVGA resolution for MK?

[Zebidee]

This may be a silly question, but have you tried adjusting the VHold pot?  How badly is it rolling?  Also I assume you are using the 401x256 AVGA resolution for MK?

This works, ironically, for that res on the arcade monitor in my Ultimate Mortal Kombat 3 cabinet. 

But you have to re-adjust the sync every time you go back to a 60hz mode.

[MK3FAN]

This may be a silly question, but have you tried adjusting the VHold pot?  How badly is it rolling?  Also I assume you are using the 401x256 AVGA resolution for MK?

This works, ironically, for that res on the arcade monitor in my Ultimate Mortal Kombat 3 cabinet. 

But you have to re-adjust the sync every time you go back to a 60hz mode.

To me, that's a dead giveaway that it's your monitor. I have the ArcadeVGA as well (FANTATSIC product btw) and I do not have this problem. On the other hand, I have a brand new monitor.

[Anubis_au]

I also have a brand new monitor but it doesn't have an oscillator to lock into the frequency of the signal coming in.

I could adjust the vertical hold to get mortal kombat to sync, but then would need to readjust when I want to play any other game.

So, it looks like I will leave MK off my list of games (no big loss anyway) and stick with the other 99.9% of CGA games to do sync.

[ahofle]

I had a similar problem with my previous arcade monitor, but it stopped rolling once the monitor warmed up.  Try letting the monitor run for 30 minutes or so to warm up and then adjust the Vhold to try and work for all resolutions.  Don't adjust it right when you turn it on.

[brandon]

couldnt you at least get MK to run at a different res with black borders?  that way you'd still have 1:1 pixels and at least be able to play the game...  I guess you could always go with the hardware stretching on a higher res but.. ugh.. I personallly HATE filtering...