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2400c doesn’t boot/freezes at welcome screen
Hello all,

One of my 2400c worked fine until yesterday it slowed down to a crawl.
I restarted, though I immediately notice no boot sound (no headphones connected).
As it booted, it kept on freezing at the beginning of the welcome screen. I tried to disable extensions, remove the extra ram, zap the pram, replace the processor card from a G3 320 to its original 180 603e…no luck. Still freezes at the same spot. It’s running 9.1 btw.

Can anyone chime in with things to try?

Thanks in advance!

A.


Posted by: Alehan on 2025-11-10 07:58:37
Here’s where it freezes.

View attachment IMG_7603.jpeg


Posted by: Alehan on 2025-11-10 07:59:21
Also, I forgot to mention that the same issue happens when booting up from os9 from a CF card PC Card drive. Freezes at the same spot

Posted by: Alehan on 2025-11-10 08:13:46
Was the PRAM battery removed before it had a chance to cause any corrosion?

Posted by: 3lectr1cPPC on 2025-11-10 09:48:25
Was the PRAM battery removed before it had a chance to cause any corrosion?
Yup. Logic board/internals are squeaky clean. Never had any leakage an does not have a PRAM battery installed.


Posted by: Alehan on 2025-11-10 09:51:35
Got it, just always the first thing to check for anyone having 2400c problems. Unfortunately I don't have much other advice to offer 🙁

Posted by: 3lectr1cPPC on 2025-11-10 09:53:27
Tried an OS other than 9.1? Maybe 8.x? I mean.. it shouldn’t make any difference.. but it could potentially highlight an area of interest depending on the outcome?

Posted by: Durosity on 2025-11-10 14:37:42
I don’t think it would make a difference, though I think it’s definitely something to do with the logic board. Maybe it needs recapping?
I swapped it with another logic board from a junk machine and it booted up. It’s all assembled now and working properly. I’ll let it run for a day or so and see…

Is there a list of caps that I could try and replace on the board?


Posted by: Alehan on 2025-11-10 14:42:01
Tried with extensions off?

Posted by: LaPorta on 2025-11-10 15:28:16
Tried with extensions off?
Yes, as I mentioned on my original post.


Posted by: Alehan on 2025-11-10 15:38:23
Yes, as I mentioned on my original post.
Sorry, I missed that within the other details.


Posted by: LaPorta on 2025-11-10 17:16:39
don’t think it would make a difference
Nor do I, but the troubleshooter in me likes to cover all the bases, especially for something simple to try!

If it’s working with another board, my gut instinct is an issue with the onboard memory. Or, possibly a chipset that’s only activated when part of the system calls on it during startup.. maybe PCMCIA?

As best I recall the 2400 uses all tantalum caps, which of course can still fail.. but they tend to get a bit explody when they do. Can you see any scorched areas on the original board?


Posted by: Durosity on 2025-11-10 17:28:08
1. try a different IDE device. i.e. try with a known-good spinning IDE disk

2. swap parts with another one of your units until you can narrow it down to a particular board.

3. pray to your favourite deity


Posted by: finkmac on 2025-11-10 20:22:41
4. Pull any additional RAM installed
5. Really look it over for any corrosion under magnification
6. Clean the dual CPU connector with Deoxit - this includes both the CPU and the motherboard
7. You can boot the board almost bare with just the LCD, CPU and motherboard connected and a small heatsink placed on the CPU. One of my 2400c worked well in this state and I kept adding casing, screws testing each time until it was finally together and working! I feel stress on the CPU daughter card, poor heat dissipation and ??? aging components makes it a very fragile notebook to get right.


Posted by: Byrd on 2025-11-11 01:34:39
4. Pull any additional RAM installed
5. Really look it over for any corrosion under magnification
6. Clean the dual CPU connector with Deoxit - this includes both the CPU and the motherboard
7. You can boot the board almost bare with just the LCD, CPU and motherboard connected and a small heatsink placed on the CPU. One of my 2400c worked well in this state and I kept adding casing, screws testing each time until it was finally together and working! I feel stress on the CPU daughter card, poor heat dissipation and ??? aging components makes it a very fragile notebook to get right.
Thank you.
I ended up switching motherboards as I had a spare laying around. Back in business.
I will clean contacts on the faulty board and reassemble once I upgrade drives…do you know if there’s any cap that might need replacing?


Posted by: Alehan on 2025-11-11 05:03:23
Nor do I, but the troubleshooter in me likes to cover all the bases, especially for something simple to try!

If it’s working with another board, my gut instinct is an issue with the onboard memory. Or, possibly a chipset that’s only activated when part of the system calls on it during startup.. maybe PCMCIA?

As best I recall the 2400 uses all tantalum caps, which of course can still fail.. but they tend to get a bit explody when they do. Can you see any scorched areas on the original board?
The board is very clean, with no apparent damage anywhere!


Posted by: Alehan on 2025-11-11 05:10:27
1. try a different IDE device. i.e. try with a known-good spinning IDE disk

2. swap parts with another one of your units until you can narrow it down to a particular board.

3. pray to your favourite deity
I swapped the logic board and the problem is gone. I’ll try and troubleshoot the faulty board and see what happens! Thanks!


Posted by: Alehan on 2025-11-11 05:11:19
And another issue after swapping logic board. The “new” one was from a 240mhz, but somehow it will freeze with any PC Card I insert. I checked the board and removed the two resistors for the Cardbus mod (which I thought wasn’t necessary on 240 models) but it’s still freezing everything. Mouse stops, and I need to restart.

It never ends!


Posted by: Alehan on 2025-11-11 14:17:39
maybe a power problem, have you checked the power supply?

Posted by: MacUp72 on 2025-11-22 03:07:15
or a cut trace on the board

Posted by: ExplorerZ on 2025-11-24 06:39:22