VOGONS


CMOS battery

Topic actions

First post, by Kouwes

User metadata
Rank Member
Rank
Member

Hi all,
I got a free 486 today. Of course the CMOS battery is leaking but doesn’t look too bad, no real damage.
Please look at the picture I attached, especially at R9. It obviously has corrosion on both soldered ends. What can I do about that?

I really like to save this machine. 486dx50 and a tseng labs ET4000 video card .
I have no idea what board it is, maybe somebody recognizes it?

Cheers, Rob

Attachments

Reply 1 of 49, by rasz_pl

User metadata
Rank l33t
Rank
l33t

Chaintech 416SX/420SX/425SX/433SC/450SC
https://theretroweb.com/motherboards/s/chaint … 5sx-433sc-450sc

Cool 92 board. Looks like I was wrong thinking 72pin simms were introduced in 1993, this board already has provision for sockets while being pre VLB. I think VLB happened in middle of 92, and this board is from March/April.

Open Source AT&T Globalyst/NCR/FIC 486-GAC-2 proprietary Cache Module reproduction

Reply 2 of 49, by Sphere478

User metadata
Rank l33t++
Rank
l33t++

I have two boards with this battery. They aren’t leaking too badly.

I store them upside down, just because I haven’t gotten to them yet.

Anyway, one day I would like to solve this issue in a very nice way.

I think there are add on boards that allow you to use a coin cell. These seem like the way to go. 🤔

Perhaps someone has a better idea?

Long story short, following.

There was a nice thread about this a few months back, anyone have that link? I don’t remember the correct search terms to find it.

Last edited by Sphere478 on 2022-09-16, 18:13. Edited 1 time in total.

Sphere's PCB projects.
-
Sphere’s socket 5/7 cpu collection.
-
SUCCESSFUL K6-2+ to K6-3+ Full Cache Enable Mod
-
Tyan S1564S to S1564D single to dual processor conversion (also s1563 and s1562)

Reply 3 of 49, by smoke86

User metadata
Rank Member
Rank
Member

Desolder/cut the battery ASAP. If you fail to do this corrosion will slowly eat the traces out.
Soak the affected area in vinegar, when it stops bubbling rinse with water and let it dry.
Check if any traced were damaged and try to run the system.

Reply 4 of 49, by Romain

User metadata
Rank Newbie
Rank
Newbie

That can be a good start - see attachement.

(but sorry I don't remind where I've donwloaded this doc)

Attachments

Reply 5 of 49, by Kouwes

User metadata
Rank Member
Rank
Member

Thanks for the replies! Well I removed the old barrel battery and cleaned the little corrosion spots.
Started the system and got into the bios but no drives are detected. It has 4 drives.
I hope that‘s because the battery is missing. I ordered a new one, external. Oh and there was also some memory error.

Reply 6 of 49, by jakethompson1

User metadata
Rank Oldbie
Rank
Oldbie

Without knowing how much background you already have with these machines...

4 drives seems like a lot unless you're counting floppy drives. Perhaps this was a server. Are they IDE or SCSI? And of course you know they won't be autodetected on its own, unless this AMI BIOS is new enough to have an "auto detect hard disk" menu and you've tried it?

There can be a memory error if the amount of memory stored in the CMOS RAM doesn't match the amount of memory detected, which would be harmless.

Reply 8 of 49, by smoke86

User metadata
Rank Member
Rank
Member

On this board you actually have to set up HDDs and FDDs manually in the bios. For HDD it is best to I put CHS data manually even if autodetecton is available. A: and B: FDDs should be set to its correct type as connected to the ribbon cable. There is no setup for CD in bios, it should be configured in autoexec.bat and config.sys using proper drivers like udvd2 and mscdex. Memory will not be detected correctly as there is no battery installed.

Reply 9 of 49, by Kouwes

User metadata
Rank Member
Rank
Member

Ok, the external cmos battery arrived today and works well. I entered the correct numbers for the quantum fireball HDD but it says HDD controller failure. Both floppy drives are configured but it won‘t boot from a dos 6.22 bootdisk.

Reply 10 of 49, by Kouwes

User metadata
Rank Member
Rank
Member

That’s the error message

Attachments

Reply 12 of 49, by Kouwes

User metadata
Rank Member
Rank
Member

There are no values on the label other than the model: Quantum Fireball 1080AT.
I found the correct values on some website though, and tested the HDD in another PC. It boots nicely into Win95.
Seems I need another controller card.

Reply 13 of 49, by smoke86

User metadata
Rank Member
Rank
Member

Well, seems you did not answer my questions. How are the drive jumpers set? Is hdd autodetecton available in bios? Which end of ribbon cable is it connected to? I instst on posting photos.

Reply 14 of 49, by Kouwes

User metadata
Rank Member
Rank
Member

No autodetection in the bios, jumpersettings are ok.
I can‘t send photos since I‘m at work right now, only have a photo of what the screen shows when I try to boot from a dos floppy.
Maybe I should try another slot for the i/o card. I had to use a lot of pressure to get it back in, same for the sound- and videocard.
The slots are not corroded only very tight.

Reply 15 of 49, by Kouwes

User metadata
Rank Member
Rank
Member

This just keeps scrolling

Attachments

Reply 17 of 49, by Sphere478

User metadata
Rank l33t++
Rank
l33t++

think a resource problem might cause that error?

board looks pretty clean doesn't seem like any battery damage.

I usually just stick the card in a bunch of times and wipe it off to clean it. Be careful about poking stuff in the slot. You can do it. just don't strain, over extend, or bend anything. and look in there to make sure you didn't leave anything.

Sphere's PCB projects.
-
Sphere’s socket 5/7 cpu collection.
-
SUCCESSFUL K6-2+ to K6-3+ Full Cache Enable Mod
-
Tyan S1564S to S1564D single to dual processor conversion (also s1563 and s1562)

Reply 18 of 49, by Kouwes

User metadata
Rank Member
Rank
Member

Tried different slots, carefully cleaned them but they were clean already.
The system posts normally. I disconnected drives a, b and d. IDE cable is ok and connected the right way 🙂.
When powering on you can hear the hdd making the usual noises.
After the HDD controller failue message, when you hit F1 the screen inverts and starts blinking.

What if the BIOS is too old and the HDD too large? After all, it‘s a 1080MB drive. But then again, the system came with this drive.

Attachments

Reply 19 of 49, by Sphere478

User metadata
Rank l33t++
Rank
l33t++

Can you source a xt-ide?

Do you have the ability to flash roms?

Any spare roms? A isa network card?

Sphere's PCB projects.
-
Sphere’s socket 5/7 cpu collection.
-
SUCCESSFUL K6-2+ to K6-3+ Full Cache Enable Mod
-
Tyan S1564S to S1564D single to dual processor conversion (also s1563 and s1562)