Arcade VGA + asusp4c800 + hantarex polostar

[deibit]

Hi.

I don't know if this is something known.. ive tried to search in the forum but i hadnt find it (so if theres an answer around there you can just insult me and point me to the right post)

Well.. my hardware setup

Hantarex PoloStar TrueFlat 29" (15, 25, 31Khz)
Arcade Vga (ati 9200)
Ultimarc J-PAC
Asus p4c800 mainboard

If i set the jumpers on the j-pac to 15khz and 31Khz everything works fine. But of course my monitor is capable of more, so I remove the 15Khz jumper and I let only the 31Khz one.

Problem is that BIOS post and setup is out of sync (once windows its loaded it works ok at 31khz 640x480 the problem its *only* during startup)

Is there a reason?

Thank you

ps- now things get worse.. now its not even working when windows its loaded (some hours ago it worked) so.. where should is start to find the problem? monitor? avga?

[deibit]

Hello it's me again.

The bad new is that i didnt fix the problem. The good new is that i have some more data:

1- If i remove all 3 jumpers from the j-pac, i can see the bios post and (tadaaa) windows works at 640x480 non interlaced (31lhz). with the trisync utility of course

BUT (always a but) it's imposible to get the screen vertical synced.. it rolls the whole time no matter how i try to tune the vertical sync knob (its too sensitive). And no.. it doesnt work joining h-sync and v-sync (it's a hantarex polostar so h-sync works as composite sync too)

2- If I set both 31khz and 15khz jumpers everythng works ok (but of course no 31khz mode)

3- If I set only the 31khz jumper no image at all

Well.. all of this sounds too weird.. anaybody has a logical explanation?

(and yes at a certain point i was able to boot in windows at 640x480 non interlaced with only the 31khz switch on.. but now not anymore...)

[deibit]

hello again..

more info.. before i experienced that when connecting the avga directly to the vga input of the monitor i get out of sync signal.. well i was wrong.

Everything goes well (no rolling, and i can see bios post and desktop at 640x480 non-interlaced) when connecting the avga directly to the monitor (and not to the j-pac) well image is not as bright (i assume that j-pac has some sort of amplifier) but thats not an issue.

Question now is... is my j-pac broken?

I would prefer to use j-pac and not direct conexion of the avga to the monitor as the j-pac seem to do a good work filtering out of sync signals.

[grantspain]

i could be wrong BUT we have polostars running direct from pc standard graphic cards,i don't think you need anything special-but phone hantarex in the u.k they will help you-polostars run 15-38k auto freq

[deibit]

Hi, yes you don't need a special graphic card if you want to run an hantarex polostar at 31khz as all vga are able to output at this frequency. But I want 15Khz as well (in fact I need 15khz more than 31khz) therefore I need a graphic card that is able to output at 15khz (like the avga)

avga is also useful but it has predefined most of the arcade resolution modes so you dont need to manually tune-up the frequencies via powerstrip or similar..

resuming.. everything its posible with a norval vga but avga is good for lazy people

[deibit]

Well.

Amdy just told me that for my special setup two possible configurations are desirable

1- Unplug both 15khz and 31khz jumpers from j-pac and connect j-pac to the avga

2- Connect the avga directly to the vga input of the monitor (he said that should be the best option)

So.. as in my case I can't get the image properly synced when the avga is connected to the j-pac, I decided to don't use the j-pac (for the video part) and to connect it directly to the monitor.

I have decided to remove the 800x600 and 1020x768 modes (just in case...)