cmos reset 502 after each startup with healthy battery hp omen

[husseljo]

With my old (swollen) battery, my Hp omen laptop always needed to showed a "CMOS Reset 502 error press enter to reboot" black screen, before it can actually start at all (of course when AC adapter plugged in). After pressing enter (rebooting), the laptop would start/function normally, however the AC has to be kept in charge or else the loop continues.

When I replaced my battery yesterday (original HP battery), to my surprise, this black error screen keeps appearing at startup. When rebooting, the laptop functions normally and the AC adapter can be removed normally (as the battery is healthy , verified by HP support assistant). This is strange as the battery, because, as I understand, in my laptop model the main battery

I should note, that I dual boot Windows 11 with Linux, so this black error screen causes the BIOS to be reset at each startup. This is very annoying, as I need to disable secure boot, in order for the dual boot to function each time.

[BeemerBiker]

Make sure your CMOS battery is good.   It may help to set windows to use UTC time instead of local.  The bios clock will then match both OS clocks.

[hussein_youssef]

As far as I know, the internal battery is supposed to maintain the BIOS and Real Time Clock (RTC) settings. Meaning, there is no standalone CMOS battery for this model (hp omen 15).

As for setting time in windows as UTC,

I already followed instructions of this link https://wiki.archlinux.org/title/System_time#UTC_in_Microsoft_Windows, by adding the corresponding DWORD to the registry.

However, windows still displays the time as the local time, which made me unsure whether it worked or not.

On another note, could a mismatch between the 2 OS clocks invalidate the CMOS checksum?

[BeemerBiker]

You are correct, there is no CMOS battery on that model.   You might want to read this discussion

https://h30434.www3.hp.com/t5/Gaming-Notebooks/HP-OMEN-15-dc1026tx-CMOS-Battery/td-p/8129724

There might be a problem if the battery is not genuine.

Can you run a battery report and see who made it?

Please run the battery report and post  the summery
you run the battery report by bringing up the administrator command windows "cmd" and running powercfg/batteryreport as shown below

After entering that explorer line you should see something like the following. You will have to click on it as it is long
https://stateson.net/docs/SP4_battery-report.html
You can use the WindowsKey + shift + S to copy and paste a small image if you want to post anything.

When I was dual booting Ubuntu and Win7 I remember having to get into the CMOS repeatedly to fix the time which then cleared the CMOS error.  I found a long time ago there are cheap motherboards, even dual xeons, on eBay  that can run Linux and I dont even  bother with a case anymore; just use plywood.

[hussein_youssef]

I ran the battery report and it seems to be fine(see image below).

Also, I should note that in order for the laptop bring me to the "CMOS RESET 502 BLACK SCREEN" on startup (as mentioned in original post), the AC adapter needs to be plugged in, otherwise it would not start. I find this strange, because if the problem is indeed in the time between the 2 OS, the battery should not have a problem starting up the laptop on its own (please correct me if I'm mistaken).

[BeemerBiker]

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@hussein_youssef wrote:

I ran the battery report and it seems to be fine(see image below).

Also, I should note that in order for the laptop bring me to the "CMOS RESET 502 BLACK SCREEN" on startup (as mentioned in original post), the AC adapter needs to be plugged in, otherwise it would not start. I find this strange, because if the problem is indeed in the time between the 2 OS, the battery should not have a problem starting up the laptop on its own (please correct me if I'm mistaken).

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Your laptop should be  booting up with the new battery.  Is that correct?  You should not need the A/C adapter to boot.

The battery report does not show a serial number.  That is suspicious.  I assume you got the HP battery from a legitimate vendor.

I believe your problem is the version of Linux you are running is changing the bios clock. According to a post on the linuxmint forum users have seen this happen even if the bios  is locked with a password.   IANE on Linux but I have had to enter the bios and simply "save" to clear the CMOS error after Ubuntu 20.04 changed the date and time.  However, I only had to do that once  and it was after installing 20.04 on a system that had been running windows 10.

When running windows and doing an update that requires a reboot, do you have to get into the CMOS?   That should not happen.  If it does happen it should never happen again once you save the settings. 

[hussein_youssef]

Whenever I have to reboot from windows or Linux there is no issue at all, I do not need to enter the CMOS at all and the laptop reboots normally.
It seems the problem is at startup only.
Yesterday, I updated the BIOS and changed the windows time to UTC
and the laptop was able to start up on its own without the "CMOS RESET 502 BLACK SCREEN" appearing at all and without the AC adapter being plugged in.
I assumed that this solved the battery issue, however today the same black screen occurred when I tried to start up the laptop (and again the AC adapter had to be plugged in, although the battery was at 43%).

I have no idea how to tackle this issue or where the problem stems from at all. Any help would be appreciated.

[BeemerBiker]

This is getting more difficult.  

Question:  

1  Did you upgrade successfully from F22 to F25 back in September?

Your battery report still shows F22 which is OK as it fixes a problem with the battery supposedly

2 Was your original battery the 3 cell version?

3 There are three A/C adapters, which one do you have?

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135 W (N17P-G0)
150 W (N18P-G0)
200 W (N18E-G0, N18E-G1, N18E-G2)

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 It is possible the 135 watt adapter cannot both charge the 4 cell battery and run the laptop at the same time.  This is just a guess.  It is suspicious that the system cannot be powered on when the battery is %43.  Possibly the battery is defective but that is unlikely given that you saw %43

Can you run another battery report?  I just sent a "friend request".  If you accept it you should be able to send me a personal message and attach the full battery report.    It is too long to post here and I might be able to spot a problem.

4 Try using only windows for several days and see if the problem occurs.  Do not bring up Linux.  I am guessing that when Linux synchronizes the time it updates the real time clock. Even a second or two change in cmos can cause the 502

5.  Do not let the laptop sleep. Try selecting hibernate instead of sleep and see if that makes a difference.

[BeemerBiker]

today the same black screen occurred when I tried to start up the laptop (and again the AC adapter had to be plugged in, although the battery was at 43%).

I have no idea how to tackle this issue or where the problem stems from at all. Any help would be appreciated.

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I believe there is a problem with the battery.  The serial number should be reported by the battery report.  You might want to read the comment under this youtube video.

https://www.youtube.com/watch?v=-YGNuf08Sfo&t=39s