Ben Eater Builds Terrible Video Cards

March 17, 2021 11:48 AM

Ben Eater builds the world's worst VGA video card and installs it in a puny computer that he also built himself.

This was posted previously, but since that time there have been some updates. If you want to build your own terrible video card, there's a website with schematics and kits.

posted by dmh (27 comments total)

Would it be more or less work to make this emit PAL/NTSC composite video rather than VGA?
posted by acb at 11:57 AM on March 17, 2021

I feel like Don Lancaster is this guy's spiritual grandfather.
posted by seanmpuckett at 12:11 PM on March 17, 2021 [4 favorites]

As mentioned in the previously, I sorta wish he'd do a companion series on troubleshooting the digital logic when it fails - here's how to use a logic probe, here's how to use an oscilloscope, here's how to use digital IO to read what was actually sent down the bus. As a nerd who knows more or less what he's doing I generally follow it, but sometimes I don't _quite_ make the same leaps, so it'd be nice to know how you figure out something isn't working because of a component fault versus user error.
posted by Kyol at 12:13 PM on March 17, 2021 [1 favorite]

"...so does Nvidia." - AMD
posted by Jessica Savitch's Coke Spoon at 12:30 PM on March 17, 2021 [3 favorites]

I understand it's impossible to get video cards right now but this is a little extreme, don't you think?
posted by Mr.Encyclopedia at 12:35 PM on March 17, 2021 [6 favorites]

Ugh, I was in until I saw he used the playmate test image. Tech and misogyny, together again.
posted by seanmpuckett at 12:45 PM on March 17, 2021 [4 favorites]

"If you end up damaging your monitor, I don't want to hear about it, don't blame me. Actually, I do want to hear about it, but don't blame me."

I appreciate the attitude that leads one to making videos that contain statements such as this.
posted by Johnny Assay at 1:09 PM on March 17, 2021 [2 favorites]

Ugh, I was in until I saw he used the playmate test image. Tech and misogyny, together again.

Most people using Leena these days have no idea it came from a 70's Playboy magazine, because it's just a girl in a hat. Hell, they probably don't even know what "Playboy" means.
posted by sideshow at 1:21 PM on March 17, 2021 [8 favorites]

There are literally billions of other images one can use to test with, many that are far superior for tone, hue and saturation testing. I'm not going to turn this post into a lecture, but not knowing the history of an image doesn't give one carte blanche to use it, especially because other people will certainly know it. "Oh, it's a pretty girl." The meaning, and the harm, is the same. Women in tech have put up with this bullshit for decades, and if people don't speak up, it won't stop. And maybe not even then, as your reply indicates. A girl in a hat indeed.
posted by seanmpuckett at 1:26 PM on March 17, 2021 [14 favorites]

Indeed, one alternative would be Lena's reprise of that image, 40-something years later, with similar clothing and pose. It would acknowledge the image's history, tiptoe around the misogynistic/objectifying legacy of its use, and also work better for testing image compression/displaying, as an aged face would contain more detail than a young one.
posted by acb at 2:56 PM on March 17, 2021 [3 favorites]

The weird part is that the image he uses in the actual video is the Gouldian Finch...
posted by kaibutsu at 2:57 PM on March 17, 2021 [1 favorite]

Yeah the thumbnail for one video has the Lena image but I don't see it in the actual video?

Anyway I don't think that Lena alone is go to make or break women in computing, but if you knew enough to go dig the image up you should know enough to realize it's got a lot of baggage and you should probably just move on and use a different image like the mandrill or something. Once you find yourself in a hole, the first thing to do is to stop digging.
posted by GuyZero at 3:22 PM on March 17, 2021 [3 favorites]

Also, for those not familiar - the Lenna story.

Recycling this image was one thing back in 1973 when there were literally very few digital photos to test image processing algorithms on, but I'm pretty sure we've gone past the limitation of needing a hand-built custom drum scanner.
posted by GuyZero at 3:24 PM on March 17, 2021 [2 favorites]

Would it be more or less work to make this emit PAL/NTSC composite video rather than VGA?

More. VGA is actually fantastically easy to generate (as opposed to transport, which is harder), because all of the signals are split - you have 3 DACs, a hsync/vsync TTL, and you're done. No carriers/clocks/anything fancy like that. You can update the pixels as often as you like, and as long as you generate that hsync pulse at 31khz or higher for "standard" vga monitors, or 15khz or higher for fancier ones that can go down to pal/ntsc analog (think amiga/atari ST output), the monitor will generally absorb your signal just fine.

Even for monochrome composite, you need to modulate the sync signals into the main signal, and don't even get me started on colourbursts....

Additionally, VGA monitors give you a LOT of leeway on your timing, that you don't get on PAL/NTSC composite inputs - again, mostly because there isn't a bunch of demodulation to be done, so the decoding logic can be dumb as hell.

Only TTL RGB is dumber (think cga/ega and friends)
posted by jaymzjulian at 3:32 PM on March 17, 2021 [7 favorites]

(related: https://www.linusakesson.net/scene/craft/ vs http://www.linusakesson.net/scene/phasor/index.php , which are both amazing, and LFT is great at explaining how this stuff all hangs together)
posted by jaymzjulian at 3:36 PM on March 17, 2021 [1 favorite]

Monochrome composite isn't *that* hard though, and many TVs are forgiving with the spec. You really just need three signal levels, black, white and sync (lower voltage than black). A couple of resistors will do it.

Color NTSC is proof that the aliens were helping us in the '50s.
posted by RobotVoodooPower at 3:39 PM on March 17, 2021 [7 favorites]

They used to say that NTSC stood for Never The Same Color.
posted by acb at 3:45 PM on March 17, 2021 [2 favorites]

They used to say that NTSC stood for Never The Same Color.

That's the problem with putting the colorburst on the back porch. Some bastard is skulking through your backyard, nicks it, and all of a sudden you got no fuckin clue what color shit's supposed to be.
posted by Your Childhood Pet Rock at 3:54 PM on March 17, 2021 [6 favorites]

The weird part is that the image he uses in the actual video is the Gouldian Finch...

It's widely suspected that the Youtube algorithm favours videos that have human faces in the thumbnail. The use of Lena is still questionable, but maybe there are algorithm-playing reasons for that too.

I remember the good old days of borrowing money I didn't need to and paying it off right away just to be correlated with good credit risk rather than someone with no credit history at all. Things are so much more complicated now.
posted by swr at 6:48 PM on March 17, 2021 [1 favorite]

Yeah NTSC is the devil's own work, even compared to PAL. Back when I worked as a chip designer designing video back ends I saw so many people screw it up (4 fields all different) I refused to build hard coded video timing generators, always built tiny microcontrollers so we could make all the bugs software and therefore fixable without a chip spin
posted by mbo at 8:46 PM on March 17, 2021 [3 favorites]

BTW NTSC killed plaid, houndstooth, stripes and was almost singularly responsible for the 80s fashion that was all solid colors.

Digital HDTV was also a much bigger deal in the US than elsewhere because the NTSC color gamut was so much smaller than PAL's that Americans literally saw stuff they'd never seen before, while everywhere else it was mostly just bigger
posted by mbo at 8:50 PM on March 17, 2021 [9 favorites]

I've loved watching this entire series and can safely say it's gone into way more depth on how computers actually operate than any of the classes for my CS/EE degree.

I'd have absorbed a lot more from those classes the first time around had any class just spent a semester building a computer from the ground up.
posted by mikesch at 7:58 AM on March 18, 2021 [2 favorites]

I'd have absorbed a lot more from those classes the first time around had any class just spent a semester building a computer from the ground up.

Tanenbaum's "Structured Computer Organization" started from ttl logic gates and working your way up to Minix. I imagine that this is what a lab for that class would have looked like.
posted by mikelieman at 9:40 AM on March 18, 2021 [3 favorites]

I love this kind of stuff, and it's right in the sweet spot of my electronics hobbying, with TTL DIP chips (plus the 6502). I never got into surface mount, and I can't get chips any more at Radio Shack. I like that every part of the video card build looked familiar and understandable to me, except I never got into EPROM writing. I questioned his math about using the 1.5K resistor with the 680Ω in parallel when one was + and the other 0, but did the math and it looks to me close enough. (Plus, it worked...)

I am envious that he always has a pre-cut, pre-stripped, pre-bent jumper wire when he needs it. (That must have taken days of off-camera work)

Looking forward to all his videos.
posted by MtDewd at 4:06 PM on March 19, 2021 [1 favorite]

I am envious that he always has a pre-cut, pre-stripped, pre-bent jumper wire when he needs it. (That must have taken days of off-camera work)

He's super tidy & organized, and I find it absolutely charming.
posted by dmh at 7:49 AM on March 20, 2021 [1 favorite]

I am envious that he always has a pre-cut, pre-stripped, pre-bent jumper wire when he needs it. (That must have taken days of off-camera work)

This.

My breadboards always look like a bowl of spaghetti. Ben Eater taught me that there is another way. :)
posted by drstrangelove at 4:11 AM on March 22, 2021 [2 favorites]

I am envious that he always has a pre-cut, pre-stripped, pre-bent jumper wire when he needs it. (That must have taken days of off-camera work)

"One of the most common questions I get is how do I make my breadboard wiring so neat and tidy. In this video I'm going to share some tips and tricks I use in my breadboard projects."
posted by Johnny Assay at 5:45 AM on April 1, 2021