Video capture.
Probably hardware mpeg decoding.

Just speculation, or have you used one?

Looks like the VMC Controller add-on for the GrafixStar range

https://docs.rs-online.com/2b84/0900766b80026d86.pdf

https://web.archive.org/web/19980131092152/ht … uctInfo/vmc.htm

PC Hoarder Patrol wrote on 2021-02-05, 03:50:

Looks like the VMC Controller add-on for the GrafixStar range

https://docs.rs-online.com/2b84/0900766b80026d86.pdf

https://web.archive.org/web/19980131092152/ht … uctInfo/vmc.htm

Awesome detective work! For some reason it never occurred to me to check archive.org.

I'm not good with video-playback accelerators... is this just for accelerating mpeg playback or some other format?

It never ceases to amaze me how many fairly complex devices were developed and manufactured (presumably an expensive endeavor back in 1995) and yet have very little sign of ever being sold or used in any significant volume.

It looks from the document like:

1. The card is designed to enable connection of some other cards of theirs that use a "VMC Connector", which is presumably one of the card-edges on the card. It sounds like a fancier proprietary version of a VESA connector.

2. It mentions MPEG, but too close to "connect other cards" and other things it probably doesn't do (video capture) to be sure about whether it actually does MPEG decoding, until...

3. It mentions that the card itself performs "digital video acceleration and scaling for the GrafixStar 300 card", which I can only assume would refer to MPEG. It sounds like some software may come with the driver, so it may have a video playing program that will be able to tell you exactly what it supports, if it doesn't support MPEG for some reason.
("for the GrafixStar 300" may mean either that their cards besides the GraphixStar 300 already hardware decode and scale video, or that only the GrafixStar 300 can be accelerated with the card. Or that they just decided to neglect to mention the other cards ranges that support the daughtercard, the 500 and 700 looks like, for this feature)

Though I guess the uncertanties in point 3 are moot if you do in fact have a GrafixStar 300, for which it should presumably accelerate decoding and scaling of MPEG. Have fun finding those drivers. Hope it isn't as annoying as the S3 Scenic MX2.

Edit: http://edv-janssen.synology.me/ct_treiber_ser … olog/readme.txt

"Installing MPEG Player for Windows 3.x
======================================

1. Make sure that you have a VESA Media Channel (VMC) enabled graphics card
installed and working in your computer."

I don't have any of the hardware in question, this was mostly just a curiosity because the information was so hard to find online. It was partially fueled by VideoLogic's interest in releasing off-beat 3D accelerators back in the late 90s. It made me wonder if anyone ever attempted to design a 3D accelerator daughterboard that was meant to connect to the VESA feature connector.

Anyway, we're really getting into some super obscure stuff here. I don't have a lot of interest in MPEG acceleration, but this is still pretty cool. I have a box of odd MPEG or other video related cards I have collected over the years. Some day I'll probably have exhausted all sound\video card related stuff and will move on to those. 😁

On this site (I believe it's run by a member) if you scroll down a bit more than half way you can find this picture with an add on card connected to the edge connector through a ribbon cable.

Hello, I have a "Videologic GraphixStar 700" VESA-Local bus VGA card with S3-968 chip and IBM Ramdac, with the VLi-120B accelerator daughterboard attached. It is connected through a very short, flat grey ribbon cable to an ISA-16 bus "Videologic Captivator Pro/TV" card which uses Philips made tuner and SAA-7110WP chip, together with the "Videologic Powerstream" codec processor. I think the flat cable-connector was called the Scenic Highway and/or "VESA MC"? Please see the attached photos.