cmos checksum error

[Croaker]

I have a really old abit tx5 motherboard. Its socket 7. It has a P233 on it. I know it's not much of a computer by todays standards. It's used by my grandmother for e-mail only. The problem is when it is cold booted. I get a cmos checksum error and it loads the bios defaults. It still works but it boots at 110mhz. So every time we must go into the bios and set it to 233mhz because it is a soft jumper in the bios. no big deal for me but for my grandmother well she never learned to drive a car kind of old school. the computer was a giant leap. Any way does anyone have an idea how to fix this I flashed the bios with the most current I could find from motherboards.org it was from 1998. Could this be as simple a battery on the motherboard. New motherboard is not an option at this point.

specs
abit tx5 AT motherboard
pentium 233mmx
64 mb mem (4 16meg 72pin)
2.5 gig WD
ISA sound
4 mb pci graphics
56k modem ?
20x cd

 

[Force]

replace the cmos battery

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