Finally mounted the CR2032 battery holder in this 486 DX - this motherboard is an older one, exclusively equipped with ISA and VLB slots, the battery in this case was not the CR2032, but rather a horrendous capacitor that was loosing acid everywhere... after a good cleaning (fortunately without damaging anything), I soldered to the contacts of the old capacitor this convenient socket that I then fitted with battery, easily replaceable at any time.

Indrid Cold wrote:

Finally mounted the CR2032 battery holder in this 486 DX - this motherboard is an older one, exclusively equipped with ISA and V […]
Show full quote

Finally mounted the CR2032 battery holder in this 486 DX - this motherboard is an older one, exclusively equipped with ISA and VLB slots, the battery in this case was not the CR2032, but rather a horrendous capacitor that was loosing acid everywhere... after a good cleaning (fortunately without damaging anything), I soldered to the contacts of the old capacitor this convenient socket that I then fitted with battery, easily replaceable at any time.

The CR2032 might get a bit warm from the trickle charge so it's probably better if you can find some recharable NiMH 3.6V battery and connect it to the leads you solderd. Or you can add a diod to hinder charging.

Indrid Cold wrote:

Finally mounted the CR2032 battery holder in this 486 DX - this motherboard is an older one, exclusively equipped with ISA and VLB slots, the battery in this case was not the CR2032, but rather a horrendous capacitor that was loosing acid everywhere... after a good cleaning (fortunately without damaging anything), I soldered to the contacts of the old capacitor this convenient socket that I then fitted with battery, easily replaceable at any time.

They are not capacitors but barrel type batteries. Quite common on older kit.

Caluser2000 wrote:

Indrid Cold wrote:

Finally mounted the CR2032 battery holder in this 486 DX - this motherboard is an older one, exclusively equipped with ISA and VLB slots, the battery in this case was not the CR2032, but rather a horrendous capacitor that was loosing acid everywhere... after a good cleaning (fortunately without damaging anything), I soldered to the contacts of the old capacitor this convenient socket that I then fitted with battery, easily replaceable at any time.

They are not capacitors but barrel type batteries. Quite common on older kit.

I HATE them! God bless CR2032 😜

Remember to use a rechargeable battery.... Or do what Hightreason has talked briefly about in one of his video's, to solder in some type of component in order to stop it from charging. On the other hand... You can get them rechargeable ones from eBay at a really low cost.

http://www.ebay.com/sch/i.html?_from=R40&_trk … 6+volt&_sacat=0

A couple of day's ago, I started playing around with my newly arrived 386 board, and found that I did not really have any sub-420 megabyte harddrive.
I began thinking in horror on that I needed to use more time on those drive overlays. They are a blessing, yet I prefer to not using them.

Anyway....
Looking in my box of drives, this little drive came to my attention. It has parameter settings for 540 and 270 (megabyte???)
Well... I connected the drive, went into the BIOS and typed in: C/H/S = 944/14/40. And it worked.
So yeah... Not all old HDD's have jumpers for things like sub-32gb and sub-8gb or even sub-2gb.
They can all be controlled by entering different parameters that are officially supported by the drive.
It was really fun to see the MB-Ratings in the BIOS go up and down, as I typed in the numbers. 😁

I'm going to play around with manually adjusting the geometry parameters one of these days. I'm not fully convinced that overlays or other proprietary tricks are necessary, although they do make life easier.

brostenen wrote:

Remember to use a rechargeable battery.... Or do what Hightreason has talked briefly about in one of his video's, to solder in some type of component in order to stop it from charging. On the other hand... You can get them rechargeable ones from eBay at a really low cost.

http://www.ebay.com/sch/i.html?_from=R40&_trk … 6+volt&_sacat=0

I've used standard CR2032.. do I have to use rechargeable one? There can be problems with the one I've used?

Indrid Cold wrote:

I've used standard CR2032.. do I have to use rechargeable one? There can be problems with the one I've used?

As far as I know, yes, you need a rechargeable battery. Non rechargeable is like putting non-rechargeable AA batteries in a chargerstation.
(And you don't really want to do that)

brostenen wrote:

Indrid Cold wrote:

I've used standard CR2032.. do I have to use rechargeable one? There can be problems with the one I've used?

As far as I know, yes, you need a rechargeable battery. Non rechargeable is like putting non-rechargeable AA batteries in a chargerstation.
(And you don't really want to do that)

But... is not the same with actual motherboards? They mount standard not-rechargeable CR2032... I've never mounted rechargeable ones, and I've never encountered problems. Is it different? I would like to understand this case

At least some boards try to charge the batteries. You can sometimes get away with it and you'll probably be fine, but I like not to take the risk on the off-chance the battery decides to pop. As such, I would probably have added a diode, though that might require a different set of batteries if the voltage drops too far - the diode will have a marginal effect on the voltage.

HighTreason wrote:

At least some boards try to charge the batteries. You can sometimes get away with it and you'll probably be fine, but I like not to take the risk on the off-chance the battery decides to pop. As such, I would probably have added a diode, though that might require a different set of batteries if the voltage drops too far - the diode will have a marginal effect on the voltage.

Thanks for the explanation... I've never thought about this possibility

For what its worth, my 386 has a coin attached with no diode and just gets mildly warm, I would suspect that if nothing else it may affect the lifespan of the battery.

I never did figure out why the battery in my old P60 got hot while the machine was running. It was a modded RTC so it should not have been connecting to power anywhere so far as I am aware, I feel kind of bad for bashing the guy who modded it. I assume the RTC was faulty (possibly from being modded somehow) because it gets unlimited 5V across those 'pins' when the system is on, I ended up taking the coin out because it burned to the touch, the internal battery had gained a charge too and it held out until I retired that system in favor of the one I have now - parts from the same guy, but no RTC and a much neater mod with no charging problems. The strange thing about that though, was that the RTC only became "Live" in the Batman board, this did not happen when I borrowed it for an ECS some time later and randomly stuck the multi-meter across the battery to see what was happening. Once again though, the current P60 is completely devoid of any issues and I'm actually thinking of moving it over to SCSI soon, also have a 66MHz (FDIV) chip on the way for it, oddly that one (I think, might have been a Socket 7 I was playing with around the same time) appears to disconnect the battery when the system is running.

My 486SX used to connect the battery with no diode directly to the old barrel's terminals, being larger AA batteries they could stomach it but still got warm and leaked some time before their expiry date. After replacing the board I used the External Battery header and the board doesn't feed power back up the wire from there.

Actually, looking at your board, there is a jumper to the bottom right of the image which appears to be "Ext Bat" with a glass diode next to it. If it does, you should be able to remove the jumper and connect the battery to Pin 1 and 4 (1 is positive, 4 is neutral. The middle pins, 2 and 3, are left disconnected in this state, the jumper that is usually there is to select the internal battery you would have removed) thus avoiding any potential problems. You may need to use a 4.5V pack if this doesn't work. If you are going to do that, do check the connector is labelled for this first though, it probably isn't wise to start connecting power to random jumpers.

Opened up the screen on my recently-acquired Toshiba T6400DX to see if I could maybe fix it. Working under the assumption the high-voltage DC-DC Converter is faulty. I've found a couple bad capacitors, now it's just a matter of getting some replacements and swapping them in.

Indrid Cold wrote:

But... is not the same with actual motherboards? They mount standard not-rechargeable CR2032... I've never mounted rechargeable ones, and I've never encountered problems. Is it different? I would like to understand this case

Different technology.... If it came with an barrel, it is Most likely rechargeable. And the board will charge the battery.

It is quite possible though, that an barrel type ia non rechargeable. I simply have not seen one yet. Even the really old Macs use rechargeable batteries.

brostenen wrote:

A couple of day's ago, I started playing around with my newly arrived 386 board, and found that I did not really have any sub-42 […]
Show full quote

A couple of day's ago, I started playing around with my newly arrived 386 board, and found that I did not really have any sub-420 megabyte harddrive.
I began thinking in horror on that I needed to use more time on those drive overlays. They are a blessing, yet I prefer to not using them.

Anyway....
Looking in my box of drives, this little drive came to my attention. It has parameter settings for 540 and 270 (megabyte???)
Well... I connected the drive, went into the BIOS and typed in: C/H/S = 944/14/40. And it worked.
So yeah... Not all old HDD's have jumpers for things like sub-32gb and sub-8gb or even sub-2gb.
They can all be controlled by entering different parameters that are officially supported by the drive.
It was really fun to see the MB-Ratings in the BIOS go up and down, as I typed in the numbers. 😁

I'm fairly certain that's just because Quantum used the same label for all the drives in the model range. I doubt putting in small C/H/S values will hurt anything, though.

brostenen wrote:

Indrid Cold wrote:

But... is not the same with actual motherboards? They mount standard not-rechargeable CR2032... I've never mounted rechargeable ones, and I've never encountered problems. Is it different? I would like to understand this case

Different technology.... If it came with an barrel, it is Most likely rechargeable. And the board will charge the battery.

It is quite possible though, that an barrel type ia non rechargeable. I simply have not seen one yet. Even the really old Macs use rechargeable batteries.

I tracked down a jumper near the ISA slots indicating two options for the battery: "normal" and "discharge" - I just set the jumper for the second option, I believe that this will not let the battery recharge.

Indrid Cold wrote:

brostenen wrote:

Indrid Cold wrote:

But... is not the same with actual motherboards? They mount standard not-rechargeable CR2032... I've never mounted rechargeable ones, and I've never encountered problems. Is it different? I would like to understand this case

Different technology.... If it came with an barrel, it is Most likely rechargeable. And the board will charge the battery.

It is quite possible though, that an barrel type ia non rechargeable. I simply have not seen one yet. Even the really old Macs use rechargeable batteries.

I tracked down a jumper near the ISA slots indicating two options for the battery: "normal" and "discharge" - I just set the jumper for the second option, I believe that this will not let the battery recharge.

As I didn't say anything... in this way, PC doesn't POST...

Indrid Cold wrote:

[
As I didn't say anything... in this way, PC doesn't POST...

This is because that is the BIOS clear jumper. 😀

Skyscraper wrote:

Indrid Cold wrote:

[
As I didn't say anything... in this way, PC doesn't POST...

This is because that is the BIOS clear jumper. 😀

I'm used to read "Clear CMOS" in that case 😜 - I believed it was for that not-charge thing 😉