Recent content by David Cook

That's great news! Happy to help. I'm glad you are keeping the SuperMac monitor. They aren't making any new ones. : )

Here are photos of the SuperMac adapters that I presume they made to allow their monitors to work with internal video: DB-15 female on one end. DB-15 male on the other end. They pass the video signals straight through but contain the sense wires inside the adapter itself. Part...

Not necessarily. I just wanted to alert you to that option. In fact, I think a lot of the other card manufacturers also provided methods of selecting resolutions (i.e. via a rotary dip switch) other than via the monitor sense pins. I believe I even have a special cable that SuperMac made to...

Most of the SuperMac video cards don't require sense lines. Instead, they rotate through a series of resolutions and ask you to press the space bar when you see an image. Then, after booting, you can use their software to pick the exact display settings you desire. The setting is then saved to PRAM.

That's very interesting. Originally, my thoughts were just as to whether or not the power supply was becoming strained, and how much extra heat was being dissipated by the total board. But, your comment makes me wonder whether I need to learn more about measuring power at across frequencies. I...

🤫 Shhh! He didn't mean that folks. Just a late April fools joke.

Has anyone tested current draw and/or voltages on the 5V line at different frequencies? I thought @JDW measured voltage at various frequencies (maybe for Spicy O Clock), but I can't find a video with that information.

Very interesting. I wonder whether the intentional LC040 mask with smaller die per process is better at overclocking, versus the faulty 040.

Does anyone know if the 68LC040 uses the same die as the 68040. I mean, is the LC just a binned version of the full 68040 where the FPU failed testing? I suspect the 68LC040 is actually a different die, given that there seems to be completely different mask versions than the full 68040. Here...

Huh. Not what I expected at all. I am so accustomed to repairing LC power supplies, I got into the habit of thinking that every Mac needed -5V for serial. 33A of 5V. Wow.

This is amazing! I have a couple of Quadra 950s, but they are just too darn loud. I assume with the PWM fans that yours is pretty quiet? The speaker looks pretty chonky. Is it facing down, though? The power supply is 550 watts located underneath? Your transistor Q111 inverts the signal for...

I saw that. :p Ebay only has the 'J' package. It looks like this needs the 'TR' package. "TC528257TR" I guess I could get a quote through Octopart

1152x870 is the best I ran across. However, with 1.5 MB of VRAM, I would think it could do more at 8-bit color.

A short update: I tried this video mode. I thought it was going to be some weird split screen or require a toggle key. The Vimage card is set to the same resolution as the internal video. When you scroll the mouse cursor to the side of the internal video screen, the image switches to where the...

Photos of the GrandVimage 17DU card. Bodge crystal and bodge diode. Nice choice of resolutions. 80 MHz clock and 1.5 MB of VRAM.