I need help! My laptop's performance becomes MUCH worse until I plug out and plug in again

Since you mentioned your battery is totally dead, have you tried starting up your computer with the battery removed from the laptop?

Well that's something i hear for the first time after all these years in tech forums.
I will suggest you start s program like Rivatuner while you play a game to see what is holding you back. You can check for any changes in cpu and gpu utilization after the plug out and in and maybe get a hint at where to look for the problem.

the battery is simply dying and the power mode is activated which affects the GPU

Have you tried adjusting the advanced options for the Windows power settings? There should be a lot of options that control when drives spin up and down, cpu and gpu power modes depending on battery level or plugged in and unplugged. I sounds like they got switched somehow and the computer is going into low power mode while it is plugged in and full power while on the battery.

https://www.howtogeek.com/393547/htg-explains-what-are-all-those-advanced-power-settings-in-windows/

Edit: Not a great solution, but I guess if you can't fix it, you could always buy a new battery and keep using the same workaround that you have been.

Can you get a new battery or otherwise charge the battery? I recall reading on the lenovo forums about a computer where the battery entirely died due to a setting somewhere. this. Do not use the driver updater they are promoting, but steps 1,2, & 4 might work?

What does lenovo's power manager say the battery status is? https://support.lenovo.com/us/en/solutions/ht500020-battery-cannot-be-charged-windows-ideapad https://support.lenovo.com/us/en/solutions/ht500020-battery-cannot-be-charged-windows-ideapad

Do you have airplane mode turned on? if yes, depending on the model, the battery will not charge Source Source #2

Please don't do anything i am about to write, if you aren't very familiarized with computers or just not a tech savvy person.

-GPU Driver issues possibly. There may be some others out there which may help. More related to switching from integrated graphics(from the CPU) to using GPU to render games.
-In addition to what AllTracTurbo said, maybe check the settings in the BIOS performance or power settings, as these may have a role.
-Another suggestion is to disable CPU Parking. I don't think this one will help much, if at all. There's a few apps that may help on this matter.
-Also it seems to me that the laptop may be using the CPU to render and not the GPU. There are drivers and maybe other tools that can help with this matter, tailored for your GPU system, if you google around enough.
-Maybe there is a new update for the BIOS that could possibly help in this matter? Don't do this unless you understand what you are doing, as you could brick your laptop.
-And last but not the least, and for this one don't recommend tinkering around unless you know what you are doing. There are tools out there that can tinker with light dimming, fan control, wifi options, etc. Usually the driver takes care of that. Tools that tinker with ACPI firmware in a low level, which the laptop usually uses to manage the fan and control the cpu and gpu temperature, along with other things. This is really for EXPERTS ONLY, WHICH I AM NOT, and i currently don't see how it could help, but hey, just throwing it out there. There would be an application where you could monitor the HEXADECIMAL Values of some of these properties, and compare them from before "your fix" to values obtained after "your fix". This is something that the drivers should do, which is why i highly suspect its to do with either the windows power settings or the drivers.
-Try pluggin your laptop in another room division just to test. The power supply or the plug where you are at, may be somewhat "faulty", even though i doubt it. Or maybe even the motherboard, but again i dont think so. I think its more related to Windows power settings, or the driver not switching to the GPU. Which i remember it being reading it being a very common issue wtth laptops.
-And if you are desperate enough, there may be "hacked" BIOS for your laptop, which may or may not help at all. I dont think they will, for starters anyway, as seen by your fix.

What is your current driver version?
And the version of the nvidia control panel application that should guide/manage the drivers settings?

your gpu usage 100% is alright .
I think you might have some preinstalled Antivir or other programm that cause this issue .
My grandma had a problem with their laptop at 1% Battery all day even if you charge ,stuttery and alot of the
i could fix the stuttery but the battery was beyond repair and still has 1% all the time in save mode or not .
My fix was to deinstall most of the preinstalled things that were useless .
Otherwise if you dont find it download a programm where you see your recources while playing and the heat of your cpu/Gpu.
and try to find the issue .
Seeing if your laptop has any critical logs while playing (Power shortage etc? would help to find your issue ) .

I am going to tell you something weird, but something that made my life difficult in a similar way.
I had a laptop with wrong charger and without battery, was not working correctly even though the specs were good.
There was an Intel driver that was making my life difficult, due to the voltage it was receiving.
New charger, battery changed the problem, but also disabling that specific driver helped before I buy the new stuff.
Search the internet based on your laptop model and maybe a combination of keywords close to my story...

Afaik crypto miners use GPU and many of them only active if you are plugged in.
If you have a kernel-mode infection, than none of your security suits would be able to catch it once windows is loaded.
Try booting from a hiren boot device and run some scanners (malwarebytes etc).

Hope it helps.

≻laptop
≻performance

If it's Asus, open up all the Asus applications and ensure you are set to always enable the GPU for processing. My wife's Asus laptop had a similar issue caused by the laptop software trying to optimize battery performance instead of graphical quality.

have you tried setting your physx to nvdia instead auto

Power settings

adjust it at your needs

How long ago did you purchase it?
And maybe i dunno just try contacting whoever the brand is from? Really depends on the brand how helpful they might be, but it never hurts to try.

That it's already there from the beginning and even reinstalled windows without a change, is not a good sign, and probably hints at something hardware related, unless it's bios but a slim chance, you can post your screenshots of relevant bios (gpu) settings here.
And since your battery seems to be dead and it was your only fix, well leaves you without much options, i say try the call or really write this off as a loss, was it an expensive one?

Sorry if I am asking something pretty basic, but english is not my native language. I understand that plug in means you have the power adapter connected to provide current, and plug out you disconnected the power adapter so your laptop was forced to use the battery, right? (if this idea is wrong, you can safely disregard the whole post).

Your solution was to disconnect external power and re-connect it. And somehow, on reconnecting, it detected that it had enough power supply to let your computer operate at full performance instead of a limited one - which seems to point to that the laptop does not detect that it is plugged in as it starts, "thinking" that it is using the battery and probably lowering performance in order to allow the battery to last longer.

As you have installed windows several times, that also pints out to that if there is a way to "tell" the laptop that you are, indeed, using your adapter and it does not need to lower your performance, that could only be done from some application directly related to your specific laptop, provided by the manufacturer.

My advice would be to check not just drivers or looking at the GPU (as my guess is that is a general performance related to power supply as a whole for your computer and not just GPU related - which would explain that changing "Power Management Mode" on Nvdia Control Panel did nothing to help), but looking out for manufacturer GUI application that let you monitor/manage your laptop. Maybe there it is a way to force it to go into/set to full power mode. But, of course, it might not have that option and rely on hardware detect, in which case you would be without options.

Just a wild idea: Have you tried to start the laptop, put it to sleep mode, then waking it again? That loads the status you were when it went to sleep, but maybe it could trigger a check for the power supply (and yes, this is a wild guess with a low probability of success; but it's a quick check so it's worth trying).

I wish you good luck on your quest!

Is there a chance you can check your laptop with another charger (of the same voltage and current), might be a problem in the cable or the brick itself.