Computer Wont Start, Have To Change Battery

Hi All,

A few weeks ago, my computer wouldn't start up....no power. I assumed it was the power supply but it wasn't. I then thought of the battery. I replaced it and the computer powered on. It was fine for about a week, then no power again. I replaced the battery and it worked again, but this time I never shut off the computer and it stayed powered for 3 weeks. Last night, my son turned off the power, and I had to change the battery again, but this time it lasted about 4-5 hours. I just now changed the battery.

I ran the diagnostics and nothing was wrong. Where should I start with identifying the issue? Is there another diagnostics program I should run?

I am running a Lenovo Ideacentre 720-18IKL :


Thanks!

 

What battery are you changing - the CMOS battery?

The CMOS battery should last years. And while you will occasionally find one that fails prematurely (I've even seen a couple brand new that were bad), lasting at least 5 years is pretty typical. Having multiple CMOS batteries fail in rapid succession would normally suggest a short in the motherboard somewhere - not good.

Note the CMOS battery is there to keep user changes to the BIOS Setup Menu and the RTC (real time clock) "alive" when the computer is "totally" off. And by "totally" off, I mean shutdown and unplugged from the wall. When simply shutdown, it "should" be in a low power standby state and the power supply should be supplying a small +5Vsb standby power to keep that data alive. At least, if the system complies with the ATX Form Factor industry standard for PCs.

So if me, I would swap in a known good power supply to see if your problem persists. That said, I cannot find any details on your PSU, only that it is a 250W. Nothing says it is ATX compliant. And the only image I can find on the motherboard does not show a 20/24-pin standard ATX power connector either. So, it would appear Lenovo may be using proprietary components and your best bet may be to take the computer to a shop. If the power supply is an external power block, you might just take that to a reputable shop for testing. Either way, power is the primary suspect here.

 

Yeah, sorry, it's the CMOS battery. I swapped the power supply, was the 1st thing I tried. Stupid thing is, Lenovo has a proprietary 10-pin, so I had to get an adapter. The power supply is working. I was thinking it was the motherboard. Is there any diagnostic software that can possibly identify the issue?

 

I wish. Even if totally ATX compliant, it would be 1 among 1000s of different motherboards and no software could be configured to test them all - especially when there are proprietary components involved.

When you say it does not turn on, do you get nothing when you press the button? That is, zero sign of life? Power button switches can go bad too. If not proprietary, there should be two leads from the back of the button to two pins on the motherboard. "Carefully" shorting those two pins with a small flat-tip screwdriver should start the computer just as pressing the power button would. If that works, you may just have a bad button switch. If that case has is a Reset button switch (not all cases do) you can pull the two wires from the motherboard going to the power button, then move the two reset wires over to the motherboard's power pins and just use the reset button as the power switch from now on.