Just saw a video from CPU Galaxy. Imm need a new crystal I think.

Are you sure? It's hard to see but there's an unpopulated Y1 and what appears to be the 14.31818 populated underneath. Might it use a clock generator chip? Any idea what the DIP switches are for?

First time I see on-board Paradise VGA, nice.

I can't help you with the jumper settings, but what happens if you try a few jumper positions? I don't think you'll wreck the board with that...

The ICS branded chip is the clock generator, I see some resistors nearby that most probably are connected to the freq control pins. They are the key to changing speed, how exactly I don't know, hopefully datasheet is available of it and it'll tell exactly how to connect the pins for the needed clock.

Here is a link to the board

https://theretroweb.com/motherboards/s/dell-d … dx2-5#downloads I believe this one is it.

https://theretroweb.com/motherboards/s/dell-s … ev.-2#downloads this board looks like it as well though.

Here is a better pic of the jumper area. Most of those jumpers are accounted for tho. The DIP switch is for configuring the onboard video. That empty Y1 next to the crystal is interesting I must say.

The 4 pins on lower right side of the clock generator specify CPU frequency (multiplied by 2).

So my guess that they are either wired through some jumpers or hardcoded.

Should be easy to find it out.

The empty Y1 position looks like a space for a larger/taller format crystal installed in the same holes as the crystal installed below it, but with the legs bent 90deg so that the body of the crystal lies parallel to the PCB.

The two pads are not connected and are there to mechanically attach the body of the crystal by soldering if required.

I'd be looking at the function of the W2 and W3 jumpers.

mdog69 wrote on 2023-01-12, 22:44:

The empty Y1 position looks like a space for a larger/taller format crystal installed in the same holes as the crystal installed below it, but with the legs bent 90deg so that the body of the crystal lies parallel to the PCB.

The two pads are not connected and are there to mechanically attach the body of the crystal by soldering if required.

I'd be looking at the function of the W2 and W3 jumpers.

W2 clears CMOS

W3 does :
I/O bus speed select SYSCLK/2 pins 2 & 3 closed
I/O bus speed select SYSCLK/1 pins 1 & 2 closed

Sounds promising, but it wont post when configured to "SYSCLK/1". It will only post when configured to "SYSCLK/2"

Odd I would expect sysclock/3 or sysclock/4