Fun with J-Pac and ArcadeVGA (in need of assistance!)

[gamingjustin]

I tend to think of myself as pretty resourceful, but there is so little troubleshooting information regarding the J-PAC and ArcadeVGA I'm not sure where to begin. I'm sure some of you here have experience with this hardware so if you're feeling generous I'd appreciate any help you can offer! Until then I'll do everything I can to solve the problem on my own so as not to waste your time...

First problem: After installing the ArcadeVGA and device drivers, and hooking up the J-Pac I cannot get a picture on anything except my arcade monitor. This is a problem for me, because I would still like to do other things with the PC; having it show up on a different display for starters. It's an Astro City monitor so it only supports 15khz and 24khz signals. How can I switch back to my computer monitor (CRT display)? Or is this not possible...

Second problem: Some games run poorly. Black Tiger plays almost identically to the real PCB I own except it doesn't scroll as smoothly. Every few seconds the screen jerks while scrolling, like the sync is slightly off or something. Also the game is supposed to run in 256x224 but the closest option I can find is 256x240 or something, so it's not quite as sharp as the real PCB. Is there a way I can set custom resolutions? Then I tried Ninja Spirit and it runs like absolute trash. Constant audio skipping, jerky framerate, choppy scrolling-- unplayable. Of course, there is no support for 384x256 resolution, just 384x288 I think... So do you have any tips to make games runs more smoothly?

I'm glad I got the ArcadeVGA and J-PAC but I can tell it's gonna take a hell of a lot of tweaking settings to get games running correctly. I could care less about MAME lag, I just want a good picture and sound. Any help will be greatly appreciated.

[jonny5]

to get rid of the tearing(the occasional chopping you referred to), just turn on wait for v-sync....

as far as the monitors go, make sure you have the jumpers on the jpac set correctly so it can accept a 31khz signal...i forget off hand bu t pretty sure its in the documentation or on the ultimarc site

as far as some games running shitty....perhaps check to see if its just not emulated properly yet.....also, depending on what model of arcadeVGA(the older ones were just radeon9200's with modded bios afaik) and what build of mame you are using....the newer builds are often more system taxing...perhaps try an older build(pre 0.130)

aside from that i would just get rid of the arcadeVGA and just use soft15khz (a software solution that does essentially the same thing as an arcadeVGA but with any ATI card or geforce cards pre 8 series, or onboard stuff).....

hope that helps a bit.....

[gamingjustin]

Thanks for the response! I figured it would just be a problem with settings in MAME, but after testing multiple builds (cabmame, mameui, mameuifx, plain mame) the results are the same. It's a problem with frequencies, and it may even have to do with the monitor itself.

The software options "sync to monitor refresh," "wait for vertical sync," and "triple buffering" all results in the same effect: a smoothly scrolling picture. So I keep "sync to monitor refresh" on for each game I try, otherwise I get ugly scrolling. Anyway, the problem is the lower the frequency the game runs at, the more the audio skips. So a game like Rastan Saga which runs at 320x240 at 60.00000Hz works near-flawlessly; the smoothness of the scrolling only skips a beat every few seconds, and the audio clips here and there. The time intervals between the video and audio "skips" are not random; happening in a cyclical fashion.

All M72 Irem games like R-Type which run at 384x256 at 55.017606Hz has audio that skips like crazy. And here is something else weird. The closest video option is 384x288 on the arcadevga (correct horizontal res, incorrect vertical), and this results in the bad audio with smooth scrolling. However, if I choose the 350-somethingx256 option (incorrect horizontal res, correct vertical) I get perfect audio with choppy scrolling!

To make it short, my computer is certainly beefy enough to run these games. The issue is some sort of communication problem between the arvadevga/j-pac and the monitor in the Astro City. It's one I have no idea how to go about fixing. I have a gut feeling even if I used the soft15khz method it still wouldn't be the way I want it-- there would still be slight video and audio problems.

[undamned]

Moving to Hardware.
-ud

[cools]

It's nothing to do with the monitor nor the card.

Enable vsync to stop tearing and that's as good as you'll get with the ArcadeVGA. With Soft15k you can get closer in more games since you can add "perfect" modes but you'll still get that stutter and audio glitching. The closer to the mode you can get the better.

The MUCH older versions of MAME don't have it, from what I recall.

[gamingjustin]

Whew... Thanks. If you hadn't said that I'd still probably be trying 500 versions of MAME and I was even considering making adjustments to the monitor if all else failed. That pretty much settles it. If I wasn't so picky about accuracy (or if I didn't know any better) the ArcadeVGA would be awesome, but I can't stomach the stuttering graphics and sound.

Looks like I'll go with my original plan and just cycle through owning 5 or 6 PCBs at a time and sell 'em off as I 1cc and get bored with them.