VOGONS


First post, by GordonFreeman

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The title pretty much sums up my question. Is there any way to get 15kHz RGB from the Voodoo 3? I'm mainly interested in using this for DOS games and 2D Windows games. Vertical scan rate doesn't matter, since my monitor should be able to handle anything. I found a program called Soft15khz that looks like it would do what I want, but I can't find anywhere to download it. Also, on the original forum post for Soft15khz it says that the front-end doesn't work on Windows 98 (for Voodoo cards), which is what I'm using. I wonder if that means it would still be possible to use it just with command-line. The post doesn't seem very clear about that. Any ideas?

Reply 1 of 28, by Joseph_Joestar

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I don't know about the Voodoo 3, but an Ati Radeon 7000 and above can do that using CRT EmuDriver under WinXP.

What do you want to play on a CRT TV? If you're targeting console emulation (SNES, Genesis, PlayStation etc.) you're better off using a modern system with a more powerful Ati card running RetroArch (it supports 15 KHz output). For DOS games, I was able to play a few of them on the RetroArch core, but I found it a bit lacking as 60Hz sometimes causes tearing and flickering.

Installing DOS drivers on an Audigy2 ZS
Using Audigy drivers with a Sound Blaster Live
OPL3 vs. CQM vs. SBLive emulated FM synth
OPTi 82C930 review

Reply 2 of 28, by GordonFreeman

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Joseph_Joestar wrote on 2020-05-05, 09:04:

What do you want to play on a CRT TV? If you're targeting console emulation (SNES, Genesis, PlayStation etc.) you're better off using a modern system with a more powerful Ati card running RetroArch (it supports 15 KHz output). For DOS games, I was able to play a few of them on the RetroArch core, but I found it a bit lacking as 60Hz sometimes causes tearing and flickering.

DOS games, mainly. Specifically, The Dig and Full Throttle, and maybe a few others. Most DOS games run at 70Hz, right? I'm fairly certain my monitor supports 15kHz at 70Hz. It's not a TV, it's a professional video monitor. This monitor also supports VGA up to XGA. I have no interest in connecting a modern system to this monitor for emulation; I want to be able to play DOS games natively. I can already do this, just not at 15kHz.

Reply 3 of 28, by imi

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GordonFreeman wrote on 2020-05-05, 09:52:
Joseph_Joestar wrote on 2020-05-05, 09:04:

What do you want to play on a CRT TV? If you're targeting console emulation (SNES, Genesis, PlayStation etc.) you're better off using a modern system with a more powerful Ati card running RetroArch (it supports 15 KHz output). For DOS games, I was able to play a few of them on the RetroArch core, but I found it a bit lacking as 60Hz sometimes causes tearing and flickering.

DOS games, mainly. Specifically, The Dig and Full Throttle, and maybe a few others. Most DOS games run at 70Hz, right? I'm fairly certain my monitor supports 15kHz at 70Hz. It's not a TV, it's a professional video monitor. This monitor also supports VGA up to XGA. I have no interest in connecting a modern system to this monitor for emulation; I want to be able to play DOS games natively. I can already do this, just not at 15kHz.

15Khz is usually always between 50 and 60Hz
if it supports VGA/XGA why not just use that?

Reply 4 of 28, by GordonFreeman

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imi wrote on 2020-05-05, 09:58:

15Khz is usually always between 50 and 60Hz
if it supports VGA/XGA why not just use that?

My monitor supports from 50Hz up to 90Hz. I'm pretty sure 15kHz at 70Hz would work, but I haven't tried it yet. I'm interested in 15kHz because I think 2D DOS games would look better at that resolution than they do at VGA. It's totally usable as is, but I think 15kHz would be better - if it were possible with my system.

An alternative that would be almost as good would be if I could just play DOS games at VGA with scanlines added - but like I said, I don't want to use an emulator, and I don't know of any way to do this in Windows 98. EDIT: I guess I could do that with an external device.

Reply 5 of 28, by imi

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most dos games run natively at 31Khz (apart from CGA/EGA)

while this is theoretically possible imo I don't think there's any easy way to output 15Khz at 70Hz as this doesn't fit in any standard, even if your monitor can display it.
all scalers I have will output either 50 or 60Hz when set to 15Khz output resolutions afaik.

but tell us if you find a solution ^^

edit: I have a scaler that lets you set ouput refresh rate at steps from 48.00 to 75.00 but as it is an upscaler only at 480p and up.

Reply 6 of 28, by GordonFreeman

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Here's another related question: excluding 3D-accelerated games, do all other DOS games run at 70Hz, or do some run at 60Hz? Is there a list somewhere of the vertical rates used by DOS games?

Reply 7 of 28, by dr.zeissler

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Joseph_Joestar wrote on 2020-05-05, 09:04:

I don't know about the Voodoo 3, but an Ati Radeon 7000 and above can do that using CRT EmuDriver under WinXP.

What do you want to play on a CRT TV? If you're targeting console emulation (SNES, Genesis, PlayStation etc.) you're better off using a modern system with a more powerful Ati card running RetroArch (it supports 15 KHz output). For DOS games, I was able to play a few of them on the RetroArch core, but I found it a bit lacking as 60Hz sometimes causes tearing and flickering.

is there also a solution for win9x ?

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Reply 8 of 28, by Joseph_Joestar

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dr.zeissler wrote on 2020-05-05, 11:22:

is there also a solution for win9x ?

Not using CRT EmuDriver as that only supports WinXP and up.

Soft15KHz might work on Win9x, but I've never used that myself. This link has some info on it: http://www.arcadeinfo.de/showthread.php?8170- … tional-Overview

Installing DOS drivers on an Audigy2 ZS
Using Audigy drivers with a Sound Blaster Live
OPL3 vs. CQM vs. SBLive emulated FM synth
OPTi 82C930 review

Reply 9 of 28, by derSammler

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GordonFreeman wrote on 2020-05-05, 10:09:

I'm interested in 15kHz because I think 2D DOS games would look better at that resolution than they do at VGA. It's totally usable as is, but I think 15kHz would be better - if it were possible with my system.

They don't, because that's not what they were made for. Unless you like more blurriness and scanlines, they won't look better. VGA on a CRT is as best as it will get with DOS games.

Reply 10 of 28, by GordonFreeman

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derSammler wrote on 2020-05-05, 11:43:

They don't, because that's not what they were made for. Unless you like more blurriness and scanlines, they won't look better. VGA on a CRT is as best as it will get with DOS games.

That's a matter of opinion, isn't it? I'm just saying what I personally want, not what's better in an objective way. Also, it wouldn't look blurrier; 15kHz on this monitor looks about as sharp as VGA, as long as the signal quality is the same.

This person claims that they did what I'm talking about, although they did it in a different way than how I'd like to do it: 15kHz RGB 200p DOS Gaming

Joseph_Joestar wrote on 2020-05-05, 11:36:

Soft15KHz might work on Win9x, but I've never used that myself. This link has some info on it: http://www.arcadeinfo.de/showthread.php?8170- … tional-Overview

The download link in that thread no longer works. Does anyone know where I can download this?

Reply 11 of 28, by imi

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GordonFreeman wrote on 2020-05-05, 12:40:

This person claims that they did what I'm talking about, although they did it in a different way than how I'd like to do it: 15kHz RGB 200p DOS Gaming

not 70Hz though.

GordonFreeman wrote on 2020-05-05, 12:40:

The download link in that thread no longer works. Does anyone know where I can download this?

https://web.archive.org/web/20150705200022/ht … t-and-Downloads

Reply 12 of 28, by GordonFreeman

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imi wrote on 2020-05-05, 12:46:

not 70Hz though.

Thanks for the link, I don't know why I didn't think of that.

The user in that other post who was trying to get 15kHz DOS games working was using Soft15khz, which doesn't support 70Hz. On the Soft15khz post, it has a link to a post that describes how to edit the registry yourself to enable custom resolutions:
https://web.archive.org/web/20111124164737/ht … -und-Grundlagen

It's in German, though. This should let me set whatever horizontal or vertical rate I want. I have a fuzzy idea that if I could figure this out, I could write a very simple program to enable or disable maybe one or two custom resolutions. I'd be happy to share that if I can actually get it working. If anyone could share a decent English translation of that guide (Google Translate tends to make mistakes), that would be very helpful, and it could also benefit other people who want to set their own custom resolutions. I'll look more into this later.

Reply 13 of 28, by imi

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well there's not much important to translate there, just use the formulas
but if you want to know anything specific just ask ^^

if you go 320x200 that would result in:
horizontal: 320 / 359 / 399 / 438
vertical: 200 / 202 / 204 / 217
pixel frequency: 438x217x70 = 6.65Mhz

that would be about 15.2kHz at 70Hz

Modeline "320x200@70" 6,65 320 359 399 438 200 202 204 217 -hsync -vsync

just need to try it I guess ^^

Reply 14 of 28, by maxtherabbit

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imi wrote on 2020-05-05, 10:35:

most dos games run natively at 31Khz (apart from CGA/EGA)

that's not exactly true, a HUGE swath of them used the 320x200 or 320x240 VGA(EGA) modes

a VGA line doubles these modes internally before scanning them out, but you could argue that displaying them undoubled on a 15kHz display was the "truth"

Reply 15 of 28, by imi

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well, yes ^^
but everything VGA was with 31khz monitors in mind, line doubling was just the method used in analog times to match that... they were never inteded for 15Khz displays afaik.
the lower resolution was just used for performance reasons I'd guess, just like we use "render scaling" today for performance reasons.

idk maybe someone with more insight into PC game developement at the time can give better reasons ^^

Last edited by imi on 2020-05-05, 15:01. Edited 1 time in total.

Reply 16 of 28, by maxtherabbit

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Games that supported EGA were clearly intended to be scanned out at 15kHz on a real CGA/EGA monitor. Just so happened that they were forward compatible to VGA as well

Reply 17 of 28, by imi

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yeah, hence why I said VGA ^^

a lot of later games that were released without CGA/EGA support were still using 320x200/320x240

like doom was designed around 320x200 but only in VGA
https://en.wikipedia.org/wiki/Mode_13h

Last edited by imi on 2020-05-05, 14:57. Edited 1 time in total.

Reply 18 of 28, by maxtherabbit

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honestly I think there was a whole lot less fretting about how users would perceive their works and a whole lot more "haha borland compiler go brrrr" amongst devs back then than people realise

Reply 19 of 28, by imi

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not at all, also I'm all for getting it on a 15kHz screen, just saying the devs probably didn't take that into account at all (especially not at odd refresh rates), and back then it was just "use a VGA monitor"

I just put VGA in one side of my extron and get 15kHz RGB out the other x3... at 60Hz that is though.