Question Bad bios chip? Laptop won't boot.

May 16, 2023
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Hello all,

I have a Dell Latitude laptop, about 9 years old. Two or three weeks ago, I started having trouble when trying to boot. I would push the power button, the power light would come on for maybe 10 seconds, then go off with no boot, no fan spin, no back light--nothing. I tried removing one of my two RAM sticks, then switched out to the other RAM stick, then tried switching which RAM port I was using, all with no results.

Eventually, I removed the CMOS/coin battery and then plugged the CMOS battery back in, and that worked--I got a successful boot. Computer worked totally normally once I was past boot. Once I've booted, I can put the computer into sleep mode and come back from sleep mode with no problem. If I would shut down completely (and maybe hibernate--can't remember for sure if I had the same problem after hibernating), sometimes I would have the same no boot problem, but sometimes it would boot as it should. Although unplugging/replugging the CMOS battery always eventually fixed it when it wouldn't boot, the problem seemed to gradually get more frequent and more stubborn. Recently, I had to shut down the computer because I was traveling, and now I cannot get it to boot at all despite many attempts.

I thought it was a dead/dying CMOS battery at first and bought a new one. No effect on the problem. Assumed that Amazon sent me a faulty replacement battery, but I recently tested it with a multimeter and both the original and the replacement CMOS batteries were outputting at 3V as they're supposed to. (Computer will also not boot with CMOS completely unplugged, by the way.) I am now thinking my bios chip is dead--I don't see why else I would get boot problems but then completely normal operation if I manage to boot successfully. I also considered a bad motherboard, but it seemed less likely to me I would get normal operation after the boot if the problem were the board and not the bios chip.

Is this most likely the bios chip going bad, or could it be a different problem? Thanks for your help.
 
Does it do the same thing whether the laptop is plugged into power or running off the battery, or is there any chance to doing one or the other has an effect on this behavior?

At 9 years old, if this laptop has seen frequent use, it's far more likely there is something wrong with the mainboard, or if equipped, one of the daughter boards, or even the primary power board, than the BIOS itself, but in any case it wouldn't matter whether it was the BIOS ROM or the board (Or any of the subsystem boards) because the probable cost of replacing any of those parts would almost certainly exceed the value of the device going forward unless you were able to find an exactly identical laptop with an entirely different problem at a price that was ridiculously low. Even an extremely low end modern model or Chromebook would likely vastly outperform that laptop by now.

And, I can't say for certain, but I'm fairly sure that the BIOS ROM in those units is not replaceable, or at least, not easily replaceable by somebody without specialized equipment and a wealth of electronics repair knowledge. Knowing the exact model of Latitude including the service tag number might help in determining a few more specifics regarding this device, but I don't think it's going to change the basic outcome which is, even if you figure out which part is bad it's probably going to require replacement of the entire mainboard which is almost certainly not going to be cost effective.

Not when you can get something that's only a couple years old and would greatly outperform that laptop, for probably between 150-200 bucks. Maybe less in many cases. Potentially even new or refurbished units at or new that price range.

One thing you might try, but if you're already having BIOS issues don't be totally surprised if it ends up bricking the machine, is simply RE-flashing the BIOS with whatever the latest available version is in case it's existing flash imprint has become faded or corrupted over time. I know that's doubtful, but I've seen BIOS become corrupted and then be fixed by being re-flashed when it was possible to do so. Still, if it at least works now so long as you remove and reinstall the CMOS battery, you might just want to cut your losses and live with it that way rather than take a chance on it being totally bricked, if this is a machine you rely on. But it's probably time to start looking at other options.
 
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DaleH

Prominent
Mar 24, 2023
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Hello all,

I have a Dell Latitude laptop, about 9 years old. Two or three weeks ago, I started having trouble when trying to boot. I would push the power button, the power light would come on for maybe 10 seconds, then go off with no boot, no fan spin, no back light--nothing. I tried removing one of my two RAM sticks, then switched out to the other RAM stick, then tried switching which RAM port I was using, all with no results.

Eventually, I removed the CMOS/coin battery and then plugged the CMOS battery back in, and that worked--I got a successful boot. Computer worked totally normally once I was past boot. Once I've booted, I can put the computer into sleep mode and come back from sleep mode with no problem. If I would shut down completely (and maybe hibernate--can't remember for sure if I had the same problem after hibernating), sometimes I would have the same no boot problem, but sometimes it would boot as it should. Although unplugging/replugging the CMOS battery always eventually fixed it when it wouldn't boot, the problem seemed to gradually get more frequent and more stubborn. Recently, I had to shut down the computer because I was traveling, and now I cannot get it to boot at all despite many attempts.

I thought it was a dead/dying CMOS battery at first and bought a new one. No effect on the problem. Assumed that Amazon sent me a faulty replacement battery, but I recently tested it with a multimeter and both the original and the replacement CMOS batteries were outputting at 3V as they're supposed to. (Computer will also not boot with CMOS completely unplugged, by the way.) I am now thinking my bios chip is dead--I don't see why else I would get boot problems but then completely normal operation if I manage to boot successfully. I also considered a bad motherboard, but it seemed less likely to me I would get normal operation after the boot if the problem were the board and not the bios chip.

Is this most likely the bios chip going bad, or could it be a different problem? Thanks for your help.
Check the CMOS battery contacts - possibly a bod contact due to oxidation, or loss of tension on the battery holder.
 
May 16, 2023
3
0
10
Does it do the same thing whether the laptop is plugged into power or running off the battery, or is there any chance to doing one or the other has an effect on this behavior?

At 9 years old, if this laptop has seen frequent use, it's far more likely there is something wrong with the mainboard, or if equipped, one of the daughter boards, or even the primary power board, than the BIOS itself, but in any case it wouldn't matter whether it was the BIOS ROM or the board (Or any of the subsystem boards) because the probable cost of replacing any of those parts would almost certainly exceed the value of the device going forward unless you were able to find an exactly identical laptop with an entirely different problem at a price that was ridiculously low. Even an extremely low end modern model or Chromebook would likely vastly outperform that laptop by now.

And, I can't say for certain, but I'm fairly sure that the BIOS ROM in those units is not replaceable, or at least, not easily replaceable by somebody without specialized equipment and a wealth of electronics repair knowledge. Knowing the exact model of Latitude including the service tag number might help in determining a few more specifics regarding this device, but I don't think it's going to change the basic outcome which is, even if you figure out which part is bad it's probably going to require replacement of the entire mainboard which is almost certainly not going to be cost effective.

Not when you can get something that's only a couple years old and would greatly outperform that laptop, for probably between 150-200 bucks. Maybe less in many cases. Potentially even new or refurbished units at or new that price range.

One thing you might try, but if you're already having BIOS issues don't be totally surprised if it ends up bricking the machine, is simply RE-flashing the BIOS with whatever the latest available version is in case it's existing flash imprint has become faded or corrupted over time. I know that's doubtful, but I've seen BIOS become corrupted and then be fixed by being re-flashed when it was possible to do so. Still, if it at least works now so long as you remove and reinstall the CMOS battery, you might just want to cut your losses and live with it that way rather than take a chance on it being totally bricked, if this is a machine you rely on. But it's probably time to start looking at other options.
Thank you for your thorough reply. The problem is the same regardless of whether I am running on the battery or have the battery disconnected and am running on AC. I believe the BIOS chip is soldered on (I don't see anything that looks like a socketed chip), and I'm definitely not experienced enough to replace that. It's not so much an issue of money--mostly, I'd like to repair it if I can because I enjoy toying with computers. I found a replacement motherboard on eBay for about $50, and I wouldn't mind dropping that much for the fun of seeing if I can get it to work, even if that's not necessarily the most economical thing to do. Does this sound like a halfway sensible thing to you, or is it probably pointless given the risk it may actually be a component board? (The motherboard I'm looking at has a slightly better processor, but seems to have the same physical arrangement of ports and, like my own motherboard, is labeled as a "Vauao la-9591p"--I wouldn't think an extremely similar motherboard would create a compatibility problem, but let me know if you think otherwise.)

A few other points, which probably don't change much, but I'll mention in case it's important.

It's a Latitude E7440, service tag GBQWH12.

I did a dual install of Ubuntu (alongside Windows) relatively recently. I used an installer, and I guess that would have changed my bios to allow me to select one OS or the other at startup. Didn't really end up using Ubuntu, so I got rid of it. Didn't think this was related, since my problems didn't start particularly close in time to the Ubuntu install and because the BIOS has been reset due to the CMOS being removed numerous times, but you'd know better than I.

Despite many attempts and CMOS unpluggings/repluggings, the computer won't boot at all for the last few days, so I can't try reflashing the bios (unless there's some way to do this without achieving boot or physically removing the chip and then resoldering that I'm unaware of). If I get it to boot, I'll probably just keep it running and never shut it down, then try reflashing bios or replacing the motherboard only when I'm completely ready to buy another computer if I brick it.

I agree that it's probably about time to face the music and start looking for a new computer. But I wouldn't mind trying to breathe one last breath of life into this one.
 
May 16, 2023
3
0
10
Check the CMOS battery contacts - possibly a bod contact due to oxidation, or loss of tension on the battery holder.
The CMOS battery is not a "free" coin battery in my laptop--it is a battery wrapped in plastic with a plug coming out of it. The plug plugs into the motherboard. I think the motherboard is getting voltage from the CMOS, because when I measured the voltage of the CMOS battery, I actually took the measurement from the board with the CMOS battery plugged in (no AC/main battery plugged in, obviously). Thank you for the thought, though!
 
The CMOS battery is not a "free" coin battery in my laptop--it is a battery wrapped in plastic with a plug coming out of it. The plug plugs into the motherboard. I think the motherboard is getting voltage from the CMOS, because when I measured the voltage of the CMOS battery, I actually took the measurement from the board with the CMOS battery plugged in (no AC/main battery plugged in, obviously). Thank you for the thought, though!

And what was the measured voltage?... the CMOS bat's 3V?... I doubt a regular non-rechargeable CMOS battery would last if it was leaking voltage to the motherboard.

What I suspect is residual static electricity, which coincidently can cause the laptop not to turn on even with a full battery and connected charger.

Check if your laptop has a power LED turned on or blinking... Either way LED on or not, try this first: disconnect the charger, and press the power button, holding it for a full minute. The power LED should have turned off... wait a couple of minutes and try turning the laptop on.

If that fails, remove the battery (and obviously the charger), and again press the power button for a minute, next reinstall the battery and turn it on.

If that also fails, remove charger, battery and CMOS battery, and repeat pressing the power button for 1 minute. Reinstall the battery and CMOS battery, and try turning it on... connect the charger if it doesn't turn on.

After that, I would suspect the CMOS battery may have a bad wire, if you can't fix it, or if it's a rechargeable CMOS battery, I would suggest getting it replaced.
 
He already replaced the CMOS battery and that didn't work. Guess you didn't read that part or missed it. Easy to do, I've done it plenty of times myself.

Removing the charger, battery and CMOS battery, and depleting the residual power to do a full hard reset of the BIOS by pressing the power button with those things removed for one to three minutes continuously, is not the worst idea. Then put them all back making sure you are using the newer CMOS battery just in case there is some intermittent issue with the older one, and see what shakes out, but I suspect this is either a BIOS ROM, motherboard or power board issue.

I think 50 bucks for a 9 year old laptop motherboard is too much, but it's not my money so that's your call. Personally, I'd look for an entire machine that maybe has a broken or cracked display, for around that price, that way if it's NOT the motherboard, and is something like the power board, you have that as well without having to then go buy another part. And that's only if you REALLY feel like this unit is worth your time. Personally, I'd probably just put THIS unit up for sale for parts like others have done and move on. But I totally understand wanting to tinker as well so I'll leave that up to you.