Presario C502 not keeping time

Hi all,
I did some maintenance on our older laptop here at the shop. It's a Presario C502US. I upgraded the RAM to max (2GB DDR2-667) and swapped out the 80GB HDD for a 90GB Kingston HyperX 3K SSD. It had Vista basic on it but I installed W7 Pro 32-bit on the new SSD.

I had this problem before with the Vista installation where it wouldn't keep time. Every time you turned it on the time would be different. I replaced the CMOS battery a couple years ago figuring that was it but it changed nothing. I read about Vista having problems so I chocked it up to that.

Well fast forward to today and W7 is doing the same thing. Also it's not just when shutting it down but even when restarting it (for updates for example). Sometimes it's off by 20 minutes and sometimes it's off by several hours. IT doesn't matter whether it's plugged in or running off the battery. IT seems as though when it shuts down the CMOS time stops completely then starts from that point next time it's turned on.

I made some changes in the BIOS to see if they were taking and they stuck so I think the BIOS is OK. I pulled the CMOS battery and checked it and it's at 2.95V so that seems OK. Any idea what the hell is going on?

For now I've simply edited the registry entry for the auto time update to make it update every 5 hours instead of every week. This has really got me scratching my head lol.

 

The CMOS battery should be a minimum of 3V. Mine is 3.14V. Believe it or not, that small difference can cause a lot of trouble. And the 'el cheapo' batteries should not be used. If you can, check the voltage before fitment.

 

OK I'll try changing that and see what happens. I noticed that even while the laptop is powered on and plugged in the time will randomly change.

Also I powered it down Saturday PM (4/18) around 2:30 PM and just powered it back on now and sure enough the time on the desktop was the time I shut it off lol. It was also left plugged into AC all weekend as well.

 

The CMOS battery isn't rechargeable. At $1 a piece it's worth replacing. And hopefully it's not anything more serious.

 

I know they're not rechargeable but I figured that it'd keep the time when plugged into AC power and not rely on the battery. Guess not lol

 

Well that did nothing. Replaced the CMOS battery, powered it on, re-synced the clock and then powered it off at 1:43PM. Powered it on just now at 2:57PM and the clock reads 1:43PM - the exact time I shut it down. I have no idea what's going on here. Also I find it funny that having the CMOS battery out for over an hour didn't reset the BIOS. The date was right just the clock had stopped where it powered off.

 

Did you set the time in the BIOS or in Windows?

The BIOS not resetting while the battery was removed for more than an hour is strange. On the motherboard there are 2 pins that need to be bridged to reset the BIOS. Check the motherboard manual and remove the battery prior to bridging the pins.

 

Well silly me realized I had removed the CMOS battery but not the laptop's battery pack lol :-o I removed both the battery pack and CMOS battery and let it sit for an hour then booted it back up and got the standard CMOS error blah blah. I went in and set the time and date in BIOS then booted into Windows. I used it for a while yesterday afternoon then shut it down fully expecting to power it on this morning and see the date/time I shut it down yesterday but to my surprise the date/time was actually correct! I guess the BIOS just needed to be reset for some reason. OH well. It's working for now lol.

 

Oh no! Sometimes we overlook the obvious. And I'm partly to blame overlooking the fact that the PC is a laptop. Let's hope the time... keeps time.