Purchase a VGA to HDMI scaler.

https://www.amazon.com/StarTech-com-VGA-HDMI- … 18371113&sr=8-8

The lowest listed resolution is 640X480. I need 320x200.

I still recommend same as before in previous thread: Atlona AT-HD500, but make sure it have 6.41a or below firmware

But, with any converter be prepared to some input lag

https://www.youtube.com/watch?v=QLcCcDpjnIk

M95D wrote on 2024-06-14, 15:46:

The lowest listed resolution is 640X480. I need 320x200.

No converter is going to handle 320x200, because that's not what gets output by the card - it gets line-doubled to 400 and the horizontal pixels aren't tied to a clock so to a display device, 320x200 appears the same as 640x400.
What you really need to pay attention to is the converter's ability to handle 70Hz input...

I use OSSC to upscale VGA and connect to LCD via HDMI. It will line-double the DOS resolutions and pass-through higher ones that your monitor can natively handle. Plus it can add scan-lines, so very close to a CRT.

OSSC seems the best option and it's not very expensive.

Does OSSC support refresh rate conversion? 70Hz to 60Hz or lower? I can't find anything about this on their wiki page.

It does not, framerate will remain as what came in. Only the vertical resolution can be multiplied with primary intent is to line double 240p/288p sources from old game consoles so they fit the limits of VGA monitors and modern display devices.

320x200 in PC stuff is line doubled by the video card and to the monitor etc. it is a 400 line source at 70Hz for games that don't try to reprogram display timings.

The most likely issue is that the TV just doesn't support 70Hz input although it can be the VGA to HDMI dongle doesn't either. You should try to see if that TV will sync to any higher refresh rates using a modern PC over the HDMI output. It should be possible to already select higher refresh rates or make custom resolutions with increased framerate for this and rule out TV being the limiting factor.

My old Dell U2412 monitor worked perfectly with all Dos resolutions including 720x400 70hz and also You could force 4:3 aspect.
I now have a 144hz LG LCD and it will not show 720x400 70hz Dos resolutions. If Your monitor cannot do 70hz at all, even in Dos then the OSSC will not help.
I use the OSSC with my LG monitor as the vertical resolution can be line doubled and that works.
You have to do quite a bit of tinkering with the settings to get a proper 4:3 aspect ratio image on a 16:9 monitor, but You can save up to 15
profiles.
I Also use it for my C64, Spectrum 2+, Amstrad CPC, Amiga 500 as they all have RGB output. RGB2HDMI is no good as it only supports 32 Colours maximum (ok for CGA and EGA).
Those Startech units are probably best avoided. I got a NOS one a few years ago and it doesn't work with 720x400 and also it forces a Black level of 16
with no option to select 0. That's why The image a few posts above is brighter than it should be.
A s far As I know there is no way to downgrade the firmware and I don't think the firmware is available anywhere even if You could.

Yeah OSSC doesn't change refresh rates. I believe LCD monitors should all support DOS modes though (70hz)... TVs OTOH don't typically expect such refresh rate unless the TV itself is designed to take PC input (quite a few TVs advertise it).

wbahnassi wrote on 2024-06-24, 05:58:

I believe LCD monitors should all support DOS modes though (70hz)...

"Support" them by skipping rendering of 1 frame out of every 7, yes...