Monthly Archives: September 2013

Leaking Batteries, Dead Clocks, Storing computers.

What goes wrong, how to fix it and how to long term store unused computers avoiding problems.


The rest of the A4000 above, not near the battery is in very good condition!

From the A5000 onwards Acorn soldered batteries[1] to the motherboard on all of their computers. If the computer is regularly used and in a normal house temperature range the batteries seem to last indefinitely. If however they are left off for months and/or subject to a wider temperature range, the battery can quickly start to chemically break down. Unfortunately it will still retain the CMOS settings whilst slowly corroding the PCB and components around it, meaning if the CMOS settings start to be lost significant other damage will normally have already have occurred. A5000 batteries are going to be up to 22 years old! And RiscPC’s 19 years with the last RiscPCs being sold in 2003.

To avoid the problem of a leaking battery when a computer needs to be put into storage we like others removed the battery which solves any battery leakage problem but when a battery is refitted we like others found that the clock often will not restart. There is a ‘kick CMOS’ utility that has been known to restart stalled clocks but hasn’t ever worked for us when a battery is refitted.

Whether you use your computer daily or want to put an old one to one side: Annually check visually the battery (For its position: see [2]) If it has started going furry replace it straight away (We can supply the battery for you to fit [3] or we can fit it, arranging collection and return if required.

Once you know that the battery is o.k. if you do need to store a computer even if only for a few weeks do ensure it is not subject to extreme temperatures we’ve have seen computers that were only stored for a few months in a loft or house attached garage batteries start to degrade. If it is for a longer period then store it on its side with PSU to the bottom should ensure that any leakage is onto the PSU’s metal case. Annually or every six months if possible plug it in and turn it on, checking that the date and time are correct. 24hours left powered would be good!

A damaged PCB may be repairable but this is a very time consuming operation with the clock chip being surface mounted and may ultimately be unsuccessful so we have in the past recommended replacement motherboards. There may come a time when motherboards become so rare (i.e. more expensive) that repairing may be economic.

If no battery damage has taken place but the clock no longer works we can replace the surface mount clock, this will cost about £45 for labour and parts but excluding collection and return.

There is now another alternative! (Cue the sales plug!)

Replacement clock module for the RiscPC, A7000+, A7000, A5000, A4000, A3020, A3010 and A3000!

Podule version for A5000, A7000, A7000+ & RiscPC (also A3000 if external Podule connector used): £26 + £2 P&P Order Page
MiniPodule Version for: A3000, A3010, A3020 & A4000: £26 + £2 P&P Order Page

n.b. we can even hire you one of the above if you are not sure it will solve your problem.
Podule clock module hire: Podule Hire
MiniPodule clock module hire: MiniPodule Hire

No additional software is required as the operating system will automatically recognise the clock and CMOS RAM
If all the Podule slots are in use on your RiscPC or A5000 we can supply a suitable solution!

Availability: Limited stocks available from stock! More stocks are available within 7-10 days

Whilst fitting the Clock Podule/miniPodule is very simple (no soldering required) you may have to disable the old clock.
More information including downloadable Fitting Instruction PDFs are here:

[1] Being a single cell we shouldn’t really call them batteries but the usage has now entered common usage and is what people search for!

[2] Downloadable Fitting Instruction PDFs have photos of the battery position on all of the computers see here:

[3] A3000/A540 CMOS battery (Horizontal mounting) can be ordered at: Order Page
A30x0, A5000 & RiscPC etc. CMOS battery (Vertical mounting) can be ordered at: Order Page