CMOS battery minimum voltage

My NS01 has gone on the blink after 10 years , but my CMOS battery is reading 2.4 v .would this be so low as to stop the operating system loading.
Any ideas tech heads.

In my experience anything below 2.7 to 2.9 and you need to change the battery as it’ll just keep resetting and won’t load anything.

Thanks Mike ,mine is well below . But i bet its not as easy as popping a new one in and all is well. But the machine is not worth the cost of sending in to reprogram.

As a rule of thumb, CMOS batteries should be replaced every 3 years as part of preventative maintenance.

Most will last over 5 years but the quoted expected lifespan is 3.

It depends how critical it is. Some will trundle on for 15 years and if swapping them out as and when they fail is acceptable then that might also be and option.

Usable voltage is generally +/-10% of stated voltage. Applications may vary.

On devices with a soldered in battery, I have generally replaced them by soldering in a battery holder to the board. There are both flat low profile ones and slightly thicker ones but with narrower pin pitch for board mounting. I have a bag of both from Radio Shack. It’s useful DIY for all sorts of home electronics with CR2032 batteries in them.

You have to reset the BIOS from the default to Naim settings after you have put in the new battery. This has been discussed here many times, in relation to Unitiserve, so you should be able to find one or two of those threads and it’s easy enough to do if you have a keyboard and monitor to connect to your server (you don’t need a mouse as well - the keyboard is sufficient).

For Unitiserve and HDX it’s a CR2032 battery. I would be surprised if NS01 were different, but I don’t actually know.

David its a CR2032 yes ive located and removed. Ive got an it mate who i will ask to help reboot. A shame to junk it . I was away to use it as a transport and got the deadly message .

Ok your mate will need a keyboard that has a PS/2 plug or USB plug on it and a monitor with a cable that has a VGA plug on it.

You change the battery, connect up the keyboard and monitor and then power up the NS01. Then interrupt the startup to get to BIOS and using the keyboard, select “Naim default” (or similar name - I forget exactly but it has Naim in it anyway) then save and exit. It should boot up and work, at which point you can turn it off, remove the keyboard and VGA connections, plug in the Ethernet cable and that should be it.

As I said before, if you search in the forum, you will find a more detailed description of what you do to get into the BIOS and what you do when you are in there.

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Well bought my cmos battery , Got myself the correct keyboard. Followed instructions ,then get message insert disc …damn after furiously searching everywhere , no sign …

Does anyone have the reboot disc for nso1 hdx…

Found these in the process.

Insert disk means that the boot sequence in the BIOS is wrong and that it doesn’t contain in the list the actual hard drive. So you should be able to correct the boot order so it starts with the internal hard drive.

Of course if it set to the internal drive, it’s always possible that the disk died. Hard drives nearly always fail on power on.

Never got less than 10 years from a CR2032 CMOS battery. Most of mine are still going strong at 15 years!

As mentioned, applications vary.

I tend to get 15 years out of static battery backup; 4 years in the servers CMOS in the data centre; and just 3 years from the CR2032 used in devices with LCD panels like the rice maker.

Having them run out and lose configuration on reboot can be catastrophic outside of ADW so at work we have a strict 3 year swap out policy. Ditto for laptops as failure to boot in front of a conference hall of 500 engineers can be similarly embarrassing and expensive.

And true to application, the less critical the impact, the more likely I am to let them run out.

It should be possible to change CMOS without losing the config. Most boards have a capacitor on the CMOS that gives 30 seconds grace period. And with ATX power or equivalent power to the board remains as long as the unit is plugged in so you can effectively hot swap it. I don’t think the Uniti Serve stuff has a PSU that supports that but I’d hope it had the expected grace period.

There is no disc to insert, so you can stop looking for it!

You have to interrupt the startup process to access the BIOS. I can’t remember what key you press as it starts up but it should say on the screen. Something like “Press delete key to interrupt normal startup”. Once it’s asking for a disc, it’s too late.

Did you search for the earlier threads like I suggested?

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Beyond me



On the first screen you show, choose “Load Naim defaults”. Then save and exit.

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