VOGONS

Common searches


First post, by Tertz

User metadata
Rank Oldbie
Rank
Oldbie

VGA had 70 Hz refresh. So if a monitor, like some LCD ones, does not support 70 Hz then we'll get an image distortion or incorrect games' speed (sometimes may to crash).
What is needed. IPS monitor, 1920x1200 (less preferably 1920x1080) with 70 Hz support on digital port (DVI, HDMI, DP). Good if it has 1600x1200 mode. It's not obligate to support 320x200, as DOSBox will be used mostly. Monitors supporting refreshes higher than 70 Hz, but not exact 70 Hz are interesting too as should to have less weird distortion.

Some LCD monitors may claim to support 70 Hz, but just convert 70->60 Hz and hence an image gets distortion. To check the presence of distortion you may by Epic Pinball Shareware. How to check possible slowdown to 6/7 of game's speed I don't know.

If someone knows models of IPS monitors with specs above, name them please.

DOSBox CPU Benchmark
Yamaha YMF7x4 Guide

Reply 1 of 42, by ZellSF

User metadata
Rank Oldbie
Rank
Oldbie

FreeSync or G-Sync monitors? I haven't tested FreeSync, but G-Sync seems to work in DOSBox.

FreeSync requires an AMD card and G-Sync requires a Nvidia card, but if money's not a huge problem then I highly recommend it.

Reply 2 of 42, by 5u3

User metadata
Rank Oldbie
Rank
Oldbie

Good question. I've been looking for such a screen for years. In my case, support for low-res modes and an analogue VGA input are also needed, because I intend to connect it to my old computers. For now, I'm using a Samsung 1920x1200 TN screen which does 70 Hz, but I don't expect it to last forever.

If you just need DVI and scaling can be done via software or drivers, there are many "overclocked" Korean IPS screens on ebay, however, I'm sceptical about the quality of these.

Reply 3 of 42, by dr_st

User metadata
Rank l33t
Rank
l33t

Some things are not clear to me. The fact that you get distortions when 70Hz is converted to 60Hz by the monitor is understandable. How can it possibly affect the game speed? Even if you assume that the game relies on the video card's refresh rate, the monitor does really take 70Hz from the GPU. The fact that it later throws away some frames and outputs 60Hz should not be "visible" to the software, and I don't see how that is even possible.

https://cloakedthargoid.wordpress.com/ - Random content on hardware, software, games and toys

Reply 4 of 42, by PhilsComputerLab

User metadata
Rank Hardware Mod
Rank
Hardware Mod

With DVI, and depending on the graphics card, like Nvidia cards for example, the video card will output at 60 Hz. Some games use the refresh rate as timing and run slower. I believe Lotus III has been mentioned. On Nvidia card, the video card scales 320 x 200 to whatever native resolution of the monitor. But it's a very soft / poor scaling. VGA is much better, as the monitor scales and it looks sharper.

I also believe that other cards, like Matrox, output at 70 Hz through DVI. But I'm not 100% sure.

For VGA, just go with a TN monitor. I haven't seen one that does not do true 70 Hz. Most can be overclocked to 75 Hz, even at 1080p.

YouTube, Facebook, Website

Reply 5 of 42, by Tertz

User metadata
Rank Oldbie
Rank
Oldbie
ZellSF wrote:

I haven't tested FreeSync, but G-Sync seems to work in DOSBox.

To check is better to try Epic Pinball, as not any game may have evident problems. There is a probability FreeSync/G-Sync will not make things better in VGA games in DOSBox, as mentioned sync technologies were intended for other (to make good look on <=60 Hz monitors for <60 fps games without ordinary vertical sync).

5u3 wrote:

If you just need DVI and scaling can be done via software or drivers, there are many "overclocked" Korean IPS screens on ebay, however, I'm sceptical about the quality of these.

I'm interested in mass model, not custom one. With ordinary guarantee, price (< $600), possibility to buy in normal shops, etc.

dr_st wrote:

The fact that it later throws away some frames and outputs 60Hz should not be "visible" to the software

As videocard may to know about 60 Hz of monitor, so there is a possibility the card will try to work in 60 Hz with VGA games. This happens on some hardware and connections according to that theme.

philscomputerlab wrote:

I also believe that other cards, like Matrox, output at 70 Hz through DVI.

The problem is to find IPS really supporting 70 Hz or at least higher. While TN is worse for me, except old games, so I'd prefer to find IPS without archaic 60 Hz limit.

DOSBox CPU Benchmark
Yamaha YMF7x4 Guide

Reply 6 of 42, by dr_st

User metadata
Rank l33t
Rank
l33t
Tertz wrote:

As videocard may to know about 60 Hz of monitor, so there is a possibility the card will try to work in 60 Hz with VGA games.

I'm talking specifically about cases where the videocard outputs a refresh rate different than 60Hz.

https://cloakedthargoid.wordpress.com/ - Random content on hardware, software, games and toys

Reply 7 of 42, by PhilsComputerLab

User metadata
Rank Hardware Mod
Rank
Hardware Mod

http://www.pccasegear.com/index.php?main_page … oducts_id=31600

144 Hz

I'm sure there will be more models coming out soon and prices dropping.

YouTube, Facebook, Website

Reply 8 of 42, by ZellSF

User metadata
Rank Oldbie
Rank
Oldbie
Tertz wrote:
ZellSF wrote:

I haven't tested FreeSync, but G-Sync seems to work in DOSBox.

To check is better to try Epic Pinball, as not any game may have evident problems. There is a probability FreeSync/G-Sync will not make things better in VGA games in DOSBox, as mentioned sync technologies were intended for other (to make good look on <=60 Hz monitors for <60 fps games without ordinary vertical sync).

So much wrong in just 4 lines.

Firstly, Epic Pinball runs at 60 frames per second (the menus run at 70 though), so if you used that to measure if your screens work at 70hz... You've made a huge mistake.

Secondly, FreeSync and G-Sync syncs your monitor refresh rate to your GPU's frame output. DOSBox outputs 70FPS? Screen refresh rate is 70hz. Sure it's not it's main purpose, but a side benefit of FreeSync and G-Sync is supporting any refresh rate up to your monitor's maximum.

Of course you need a FreeSync or G-Sync monitor that supports 70hz+, but there's a few IPS 120hz that supports it. Not monitors I'd buy exclusively for DOSBox, but if you're also a PC gamer... So worth it.

Reply 9 of 42, by sgraffite

User metadata
Rank Newbie
Rank
Newbie

I have a Yamakasi Catleap Q270 which can do 110Hz. More than that it starts to get artifacts on the screen. It is a 27" 2560x1440 IPS display. I've never used it for anything retro though.

Reply 10 of 42, by Tertz

User metadata
Rank Oldbie
Rank
Oldbie

HP Z24i allows user video modes. Maybe there can be inputed 640x400x70, as it supports 720x400x70 Hz and has enough MHz for this. Probably some other IPS has such possibility too. This needs to be checked as a possible solution.

I've found some IPS support 720x400x70 Hz. Unfortunally DOSBox has the issue with aspect ratio in 720x400 fullscreen mode with 320x200 (or 640x400) source.

ZellSF wrote:

Epic Pinball runs at 60 frames per second

I tested this game on practice: set 60 Hz mode on my CRT and game in DOSBox had distortions, then set 70 and that distortions have gone.

FreeSync and G-Sync syncs your monitor refresh rate to your GPU's frame output.

Until I have no practice results that these technologies help with DOSBox and 70 Hz VGA games, I have no enough base to be sure. It's just an acceptable hypothesis still. Technically it's possible, but there may to be limitations for maximum vertical Hz. So if a monitor officially supports 640x480x60 Hz, it does not mean it will allow 640x480x70 Hz with x-Sync technologies enabled, even if hardware physically can handle it.

Of course you need a FreeSync or G-Sync monitor that supports 70hz+, but there's a few IPS 120hz that supports it.

I don't like the idea to buy an LCD by mail from a company without a guarantee in my place. So I'm looking for mainstream producers and models. Among those I saw info only about $800 Acer IPS with 144 Hz but it has higher resolution, and also the diagonal and price are surplus.

Last edited by Tertz on 2015-06-12, 00:09. Edited 1 time in total.

DOSBox CPU Benchmark
Yamaha YMF7x4 Guide

Reply 11 of 42, by Lo Wang

User metadata
Rank Member
Rank
Member

Software does not necessarily have to output a framerate to match the refresh rate of the display mode it's running at, neither is it required to be a multiple thereof.

E.g. Build engine games ticked at 60fps but had native mode 13h support.

Only CRT's are prone to "distortion" because both picture dimensions and aspect ratio are entirely dependent on the timing signal it's fed by the video hardware, not on an internal clock. All you get on flatpanels is scaling error and that is completely unrelated to refresh rate.

"That if thou shalt confess with thy mouth the Lord Jesus, and shalt believe in thine heart that God hath raised him from the dead, thou shalt be saved" - Romans 10:9

Reply 12 of 42, by ZellSF

User metadata
Rank Oldbie
Rank
Oldbie
Tertz wrote:
ZellSF wrote:

Epic Pinball runs at 60 frames per second

I tested this game on practice: set 60 Hz mode on my CRT and game in DOSBox had distortions, then set 70 and that distortions have gone.

I've also tested this. It runs perfectly smooth without any distortions at 60 frames per second. That's the framerate it outputs.

It should not look better at 70hz, that's a problem with your setup. I don't doubt it as I remember having similar results myself, but still, you should pick a better testing game: a 60 FPS game running at 60hz is not a good way to test 70hz support.

Tertz wrote:

Until I have no practice results that these technologies help with DOSBox and 70 Hz VGA games, I have no enough base to be sure. It's just an acceptable hypothesis still.

So until you have a FreeSync or G-Sync monitor you will avoid buying a FreeSync or G-Sync monitor? There's a problem with that way of thinking...

Reply 13 of 42, by Tertz

User metadata
Rank Oldbie
Rank
Oldbie
Lo Wang wrote:

Only CRT's are prone to "distortion"

I also tested Pinball in DOSBox on TN LCD with 60 Hz and have gotten same distortion.

ZellSF wrote:

I've also tested this. It runs perfectly smooth without any distortions at 60 frames per second.

It runs smooth on my CRT and TN LCD (2 different PCs) in 60 Hz mode, but both have regular distortion line during vertical scrolling in the game. DOSBox 0.74 settings are default.
While there is no distortion line in 70 Hz on CRT. My LCD does not support 70 Hz in any mode so I can't check is it same with it.

Pinball wich uses 320x240 (and hence in theory is expected to have 60 Hz) is not the best application to test glitches of mismatch 70 Hz VGA game and 60 Hz monitor's mode, but I don't know better. At least it's suitable to check CRTs.

So until you have a FreeSync or G-Sync monitor you will avoid buying a FreeSync or G-Sync monitor?

Several authoritative sources would be enough to take seriously your supposition. If such will try on practice and say -Sync really allows higher than official refresh on IPS (at least mode 640x400x70 Hz), then I'll believe it fits my needs. I'll recall: -Sync technology was made for fps bellow refreshes.
As for now there is no IPS with -Sync wich fits my needs (producer, price, size), so there is nothing even to check. While the only IPS with -Sync I know officially supports high refreshes up to >=120 and this seems to become norma, so your hypothesis most probably will stay useless.

There's a problem with that way of thinking...

There is a problem with the way you interpret what others think and how you perceive the importance of hypotheses. But I suppose shortcomings of your thinking are not important for the theme.

DOSBox CPU Benchmark
Yamaha YMF7x4 Guide

Reply 14 of 42, by ZellSF

User metadata
Rank Oldbie
Rank
Oldbie
Tertz wrote:

So until you have a FreeSync or G-Sync monitor you will avoid buying a FreeSync or G-Sync monitor?

Several authoritative sources would be enough to take seriously your supposition. If such will try on practice and say -Sync really allows higher than official refresh on IPS (at least mode 640x400x70 Hz), then I'll believe it fits my needs. I'll recall: -Sync technology was made for fps bellow refreshes.
As for now there is no IPS with -Sync wich fits my needs (producer, price, size), so there is nothing even to check. While the only IPS with -Sync I know officially supports high refreshes up to >=120 and this seems to become norma, so your hypothesis most probably will stay useless.

Obviously FreeSync/G-Sync monitors won't support higher than their max refresh rates, a 60hz FreeSync/G-Sync monitor won't support 70hz. I'm not sure where you think I wrote that.

A 120hz FreeSync/G-Sync monitor however will support everything below 120 FPS, including 60 and 70 FPS games (the monitors might not sync to that refresh rate, but it's not important for DOSBox).

Sad that your budget doesn't allow it... if you can wait I expect price wars on this soon.

Reply 15 of 42, by Lo Wang

User metadata
Rank Member
Rank
Member
Tertz wrote:
Lo Wang wrote:

Only CRT's are prone to "distortion"

I also tested Pinball in DOSBox on TN LCD with 60 Hz and have gotten same distortion

Software malfunctioning/crashing while synchronizing to an unsupported refresh rate, that's perfectly possible, but it shouldn't cause distortion, whatever it is that you've observed.

Since software can indeed malfunction under the aforementioned circumstances, you could in theory get distortion if it were programmed in a non-conventional kind of a way, but that's something I've never seen myself.

The other possibility is a throwaway quality monitor that doesn't even know how to properly detect and accommodate a 70hz signal, but that too would be very unlikely, specially when dealing with long standardized modes.

In any event, if you run Pinball without vsync and it does still distort, we could at least narrow it down to a hardware issue.

"That if thou shalt confess with thy mouth the Lord Jesus, and shalt believe in thine heart that God hath raised him from the dead, thou shalt be saved" - Romans 10:9

Reply 16 of 42, by jonnyjr

User metadata
Rank Newbie
Rank
Newbie
ZellSF wrote:

...
Firstly, Epic Pinball runs at 60 frames per second (the menus run at 70 though), so if you used that to measure if your screens work at 70hz...
...

Actually, DOS games do not run at exactly 60 or 70 hz, but at 59.713 or 70.086 Hz... use DosBox video recording to get the actual screen refresh rate(s) the game is using.

I've used Nvidia custom resolution to set my refresh rate to these refresh rates, and when running DosBox in a window (I haven't found any way to force DosBox refresh rate in fullscreen) I get very smooth playback without stuttering. However, if the game changes refresh rate (as Epic Pinball and Jazz Jackrabbit does), I have to select the refresh rate that is used most of the time.

I'm curious about whether FreeSync/G-Sync will solve these problems or not, so I'm going to buy a FreeSync monitor and check it out in the near future.

Reply 17 of 42, by PhilsComputerLab

User metadata
Rank Hardware Mod
Rank
Hardware Mod
jonnyjr wrote:

I've used Nvidia custom resolution to set my refresh rate to these refresh rates, and when running DosBox in a window (I haven't found any way to force DosBox refresh rate in fullscreen) I get very smooth playback without stuttering.

Nice!

How do you configure DOSBox with the refresh rate?

YouTube, Facebook, Website

Reply 18 of 42, by jonnyjr

User metadata
Rank Newbie
Rank
Newbie

I haven't found any way to configure DOSBox to use a specific refresh rate. This is why I've made a custom resolution with the refresh rate I want with Nvidia's "custom resolution" functionality, selected this as the desktop resolution/refresh rate and started DOSBox in windowed mode.

Edit: A nice webpage to check what your actual refresh rate is: https://www.vsynctester.com