Thread

Color classic - Put in 575 motherboard

Color classic - Put in 575 motherboard Hardware 14 posts Jul 9, 2007 — Jul 14, 2007

#1 Mon, 9 Jul 2007 - 23:38

I put in a 575 motherboard in my CC. I did no other modifications. I wanted to make sure the board was ok. It chimed, and I got a grey screen - which was good but the hard drive spins up then spins down after a few seconds and won't spin back up and I get the blinking question mark. I put the stock mobo in with the same result.

Any ideas? I don't have any boot disks right now - at least for a few days. I had 7.1 on the internal 80mb drive.

#2 Tue, 10 Jul 2007 - 00:14

The LC575 board is looking for 640 x 480, which the Colour Classic lacks in stock form. You can either do the "Mystic" mod to enable 640 x 480 output, or there is a software hack to get it to work with 512 x 384. Without either of the above, it will not boot.

http://www.stuartbell.dsl.pipex.com/PowerCC/

JB

#3 Tue, 10 Jul 2007 - 06:00

you should look through the CC faq:

http://www.colourclassicfaq.com/

there are described all mods you may need to get it worky...

#4 Tue, 10 Jul 2007 - 15:19

I've read the FAQ - very informative. I'm in the process of doing the VGA mod right now... Then it should work properly

#5 Tue, 10 Jul 2007 - 16:53

Welcome to the addictive Mystic upgrade community!

#6 Tue, 10 Jul 2007 - 17:18

Last night I got to the point of needing to change the sense wires. I already Isolated pin 8 and jumped pin 8 to 12 like it says. I just need to find a good way to isolate pin 20 on the analog board since I don't have J78

#7 Wed, 11 Jul 2007 - 02:47

can't you carefully cut the trace with some suitable tool (dremel or razor)?

#8 Wed, 11 Jul 2007 - 13:44

Yep, did that. now I'm on soldering pin 20 to 24... thats a lot tougher than I thought. I am rather impatient though.

#9 Wed, 11 Jul 2007 - 19:35

I sooo badly want to do the VGA hack on my Mystic, but I have no soldering experience and am a bit timid about it.

#10 Wed, 11 Jul 2007 - 21:15

If you can avoid doing it, CT, I would avoid it, just to keep your CC in stock condition. I have a great takky with dual-PCI, TV tuner and everything, and I wish I'd kept it stock. :-(

I scored another CC and am going to (eventually) build a huge Mystic out of it, but I'll be doing the solder-the-575-board hack to force the rez down, rather than doing the VGA hack. This is just to keep from modifying the CC (can always swap the stock board back in!)

#11 Thu, 12 Jul 2007 - 05:31

If you can avoid doing it, CT, I would avoid it, just to keep your CC in stock condition. I have a great takky with dual-PCI, TV tuner and everything, and I wish I'd kept it stock. :-(
I scored another CC and am going to (eventually) build a huge Mystic out of it, but I'll be doing the solder-the-575-board hack to force the rez down, rather than doing the VGA hack. This is just to keep from modifying the CC (can always swap the stock board back in!)

I intended the CC to be my little portable X terminal, but at less than 640x480 it is pretty sad.

Or maybe I'm a little confused as to which video hack we're discussing? I'm wanting to do the low voltage one--less stress on components.

#12 Fri, 13 Jul 2007 - 14:03

I am in the process of doing the VGA mod on my CC.I might've goofed

First I isolated pin 8 with a dremmel type tool. Then I soldered a wire from pin 8 to pin 12.

I then Isolated pin 20 on the analog board by dremmeling the pin towards the connector

I then dremmeled pin 25 at the bottom (towards the connector) to isolate that (or so I assumed). I then soldered pin 20 to (d'oh) pin 26. I got video, but it was really messed up, and the OS 7.6 boot CD gave me a bomb (bus error) with the LC 575 motherboard. Noticing I didn't solder pin 20 to pin 24 I dove in again to fix that.

I then soldered pin 20 to pin 24 with some wire and put everything back together. I now have NO video...

Here's what I thought might have caused it:

1) pin 25 is not isolated because I only isolated it on the bottom, not the bottom and top as pictured here:

http://www.colourclassicfaq.com/img/connector.jpg

2) I messed up the solder joints surrounding pin 26 through pin 18 as I did get solder very hot around there. I didn't have the right tip on the first time. I DID find my fine tip though...

3) I broke the CRT in some manner...

I've checked to make sure I plugged everything in. I just don't know where else to check, or how to check if I've killed my color classic.

I should note that my analog board does NOT have J78/79

Any tips or advice is appreciated!

#13 Sat, 14 Jul 2007 - 04:40

nobody?

#14 Sat, 14 Jul 2007 - 05:08

Not enough info to say much.

Things to try: Carefully double-check your work.

If you can't see anything wrong, restore to the original configuration. If it doesn't work, then you likely borked something when you powered it up with the connections incorrect.

The crt can be damaged physically. It's highly unlikely to have been damaged by a wiring error. So unless you bumped the neck and cracked it (with an accompanying loud, long hissssss), the crt itself is the last thing to worry about.