sofakng wrote on 2021-07-02, 20:00:

If I don't have space for a CRT monitor, is there any reason to purchase a 4:3 LCD instead?

For example, I have 1080p and 4K LCD monitors but I'm curious about 4:3 LCDs such as the Dell 2007FPb, etc.

Can anybody explain the benefits (besides the aspect ratio) of using a dedicated LCD monitor?

See this thread Good 4:3 LCD Monitor

EDIT: And this one Widescreen monitors and 4:3 aspect ratio compatibility thread

Using a monitor that

a) supports both 60Hz and 70Hz and also does not skip frames

b) even if not 4:3, has the ability to force 4:3 mode (useful for proper aspect ratio at 320x200) . (I don't care about black nars on the sides of a 16:10 or 16:9 monitor)

c) works with OSSCs oddball line doubled modes

Is my personal preference .

My choice is currently OSSC with a Philips 252B9 which is 16:10 . There are of course other options and checks boxes a, b and c .

I also have a Dell 2007FPB variant, but it skips frames when fed 70Hz and also has a rather worn fluorescent backlight. The 70Hz frameskipping issue is common to practically all 4:3 IPS displays (only recently have IPS panels with support for more than 60Hz become available).

Thanks for the information and links!

Does the Philips 252B9 support 70 - 75 Hz? (it looks like it only supports 60 Hz)

I've looked through the threads you linked and there's quite a bit of information but it seems like no single answer (for anything reasonably available anyways).

Have you seen the ASUS PA248QV? The MiSTer forums seem to recommend it and it supports 75 Hz (without frameskipping I think?).

sofakng wrote on 2021-07-03, 02:27:

Thanks for the information and links! […]
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Thanks for the information and links!

Does the Philips 252B9 support 70 - 75 Hz? (it looks like it only supports 60 Hz)

I've looked through the threads you linked and there's quite a bit of information but it seems like no single answer (for anything reasonably available anyways).

Have you seen the ASUS PA248QV? The MiSTer forums seem to recommend it and it supports 75 Hz (without frameskipping I think?).

The PA248QV looks interesting , but according to https://dlcdnets.asus.com/pub/ASUS/LCD%20Moni … 8QV_English.pdf , page 3-5 says

1Aspect Control: Adjusts the aspect ratio to full, 4:3, or OverScan.
24:3 is only available when input source is in 4:3 format. OverScan is only
3available for the HDMI input source.

which gives the impression that this is not a true 4:3 mode, but possibly a so called "aspect" mode (where the display essentially tries to guess at what should be displayed as 4:3) and that 320x200 (640x400) might not be displayed as 4:3 . I could be wrong, of course, but the language used in the manual raises my suspicions on that front .
EDIT : Looks like my fears about the PA248QV's unability to do 320x200 (640x400) at 4:3 aspect ratio are confirmed here --> https://www.reddit.com/r/dosgaming/comments/h … iably_force_43/

1With this new found idea I purchased an ASUS PA248QV, a 1920x1200 75Hz display with VGA input and a force 4:3 option. Sounds great! What's not to like? Well, it can force 4:3 unless it believes it's being fed a 16:10 resolution. Guess what ratio 320x200 truly is? Yeah.

I should also mention that CDE uses an AOC G2590PX (TN) that also handles 70Hz at least and has an explicit 4:3 mode . At last notice, he is very happy with it .

As for the Philips 252B9, hopefully, the following posts (and corresponding quotes) answer most of your questions about it . Feel free to ask more .

Excerpt from 252B9 manual :
https://www.download.p4c.philips.com/files/2/ … _11_dfu_aen.pdf
Page 19 :

Resolution & Preset Modes
Maximum Resolution
1920 x 1200 @ 60 Hz (analog input)
1920 x 1200 @ 75 Hz (digital input)

Recommended Resolution
1920 x 1200 @ 60 Hz

Re: Good 4:3 LCD Monitor

1Yes, it does at least 70Hz . I tested it with vsynctester.com on a modern machine at 1920x1200@70Hz and 1600x1200@70Hz on a Windows 98 SE machine with PixperAn .
2
3I also tested 1600x1200@75Hz on a modern machine .
4
5I imagine 1920x1200@75Hz without frameskip would work too, but I do not remember if I tested that specifically. EDIT: Confirmed working at 1920x1200@75Hz

Re: Widescreen monitors and 4:3 aspect ratio compatibility thread

1Philips 252B9 preliminary tests (over HDMI) results are in :
2
3The "good" :
4a) the 4:3 mode works like it should (including with 640x400 , 720x400 and their line-doubled versions)
5b) 75Hz and 70Hz at 1600x1200 (reduced blanking) work without skipping frames (tested using vsynctester.com on an RTX2070) and though 70Hz is not in the monitor's EDID it works well when forced
6c) As mentioned in a), OSSC's line-doubled modes work without issue, this includes 1200x800 ,1440x800 and 1280x960 at either 60Hz or 70Hz
7d) 1600x1200@70Hz with reduced blanking thanks to a modded EDID on an EDId emulator works fine with my Geforce FX 5900
8
9The "bad" :
10e) When running at >60Hz at 1600x1200 , uniform surfaces are slightly textured . This not apparent at 60Hz or when running lower color depth DOS modes at 70Hz . My guess is that this is an FRC limitation on the panel when running high refresh rates (several 6-bit +FRC LG IPs panels I have display the same effect ).
11
12The "ugly" :
13f) The screen has one hot red sub-pixel about 5cm (2 inches) from the left and about 1cm (3/8 inch) from the bottom . According to the manual, this is within the "acceptable" limits for such defects, so no warranty claims can be made .
14
15Verdict : Except for f) , this monitor is practically perfect for 4:3 retro needs when used with an OSSC and VGA source as well as, optionally, an FX 5900 with an EDID emulator for 70Hz .
16
17Food for thought : I now have 2 monitors with, reputedly, the same model LCD panel. One has a sub-pixel defect but has a 4:3 mode whereas the other has a flawless panel but no 4:3 mode. Need I say more about what I'm thinking about ? 😀

Re: Widescreen monitors and 4:3 aspect ratio compatibility thread

1I just re-tested the Philips 252B9 at both 1600x1200@70Hz and 1920x1200@75Hz and also my Acer EB321HQ at 1920x1080@70Hz with vsynctester.com . In all cases, the beach scene scrolled very smoothly .
2
3Off-topic: I will add that, IMHO, the Acer EB321HQ is a great and incredibly cheap (I got it at 230 CAN$ on special about a year and a half ago) 32-inch 2K IPS monitor. BOE makes some really nice but inexpensive panels . I can't find a datasheet for it, but it seems to handle 70Hz better than panels officially rated for it . Too bad it does not have a 4:3 mode .

EDIT: Corrected typo

Wow -- thanks for that incredibly detailed information!

Are you upscaling the DOS output resolution (ie. 320x200, 640x480) to the native resolution of 1920x1200?

Can you use an OSSC (or similar) to achieve native resolution so everything looks sharp?

sofakng wrote on 2021-07-05, 02:25:

Wow -- thanks for that incredibly detailed information!

Are you upscaling the DOS output resolution (ie. 320x200, 640x480) to the native resolution of 1920x1200?

Can you use an OSSC (or similar) to achieve native resolution so everything looks sharp?

The devil is in the details, as they say . I actually purchased and tested about 5 or 6 digitizers/scalers before I settled on the OSSC and have purchased 3 monitors, before I settled on the Philips 252B9 . One of my objectives is to help other people avoid at least some of the trial and error that I had to go through .

My setup with the OSSC and Philips 252B9 is exclusively used for retro purposes and thus always in 4:3 . The setup is as follows :

a) My monitor is set to 4:3 mode, so it behaves as if its native resolution is 1600x1200 and black bars are visible on each side of the screen (unavoidable in4:3 mode as monitor is 1920x1200)

b) Main retro VGA card for DOS use is a Voodoo 3 3000 with an analogue VGA output connected to the OSSC

c) OSSC is set to line2x mode

d) Point c means that 320x200@70Hz, which is actually line-doubled by the VGA card to 640x400@70Hz on output (all VGA cards do this by default) is line-doubled to 1280x800@70Hz by the OSSC

e) Point c means that 720x400@70Hz (VGA text mode) is line-doubled to 1440x800@70Hz by the OSSC

f) The OSSC cannot distinguish between d and and e (no scaler or monitor can), so sampling mode on the OSSC must be switched accordingly on the OSSC manually (to switch, 2 buttons to press on OSSC remote control if using presets)

g) Point c means that 640x480@60Hz is line-doubled to 1280x960@60Hz by the OSSC

h) Any higher resolution than 640x480 is digitized and passed through as is by the OSSC

i) due to a limitation of the OSSC, it is usually not possible to output 320x200@70Hz (line-doubled by the VGA card to 640x400@70Hz) as 1600x1200@70Hz, because this essentially "overclocks" (runs out of spec) the OSSC and usually generates artefacts on screen, which is why I use d . This is a bit of an over-simplification . I can probably link to a previous that explains it better if I can find it .

j) due to a fundamental limitation of the OSSC, it is not possible to output 640x480@60Hz as 1600x1200@60Hz. This is because the OSSC is a line doubler (multiplier), not a scaler, so only integer multiples of a given resolution are possible on output and output resolution of the OSSC is constrained by the 165MHz limit of its TMDS . This means that 1280x960@60Hz is that the maximum you can from 640x480@60Hz, as 1920x1440@60Hz (line3x) would be higher than the monitor's 1200 line maximum and would also be above 165MHz and thus out of spec for the OSSC (if the OSSC even allowed it).

Due to the above points, the OSSC can only take you part of the way to the monitor's "native" resolution of 1600x1200 (when used in 4:3 mode). The rest of the way is achieved by the monitor's scaler . IMHO, that typically still looks extremely sharp and definitely better than any other alternative when using an LCD monitor . See here for a picture of the monitor/OSSC combo running Doom in my setup : Re: Widescreen monitors and 4:3 aspect ratio compatibility thread

EDIT : Corrected typo

My Packard Bell/NEC FT700 LCD monitor is great for Dos and Windows 3.x stuff...😉

darry wrote on 2021-07-03, 03:00:

I should also mention that CDE uses an AOC G2590PX (TN) that also handles 70Hz at least and has an explicit 4:3 mode . At last notice, he is very happy with it .

It is a great monitor with lots of inputs although perhaps less suitable for DOS than the 252B9 which can do 1600x1200. I like the G2590PX for its 1:1 mode so that 640x480 is doubled by the OSSC as 1280x960 and shown pixel perfect. It also provides two 4:3 modes, 17" and 19" but they are not pixel perfect when showing doubled 640x400 boxed into 4:3. Also the G2590PX max refresh rate is 144 Hz and is Freesync compatible so it's pretty great for first person games.

Speaking more generally I went from using some old Dell 17" 5:4 to using HP 20" widescreen as part of working from home last year, none of them ideal for gaming but all free 😉
I was never a purist and 5:4 was close enough to 4:3 for my tastes.

Only thing I've lost is the ability to display anything below 640x480 correctly. Some games like Warcraft 1 don't look that bad stretched out while others like Doom look terrible.
In fact the new screens do have a nicer image overall, seems improvements have been made since the Dells were made 10+ years ago
The old Dells didn't support 60hz meaning I couldn't play some Matrox M3D games but apart from that the Dells were good enough for my needs.