This is pretty common with the 980M so it's probably a vBIOS issue. I'll see if I can find one that is more suitable for you. 

Hi @ArchangelosGG  welcome to this free user to user Alienware laptop discussion forum. This is not Dell Support. 

Installing a different GPU card might have inherited the old GPU fan driver. Please go to Device Manager and delete GPU fan driver, then Restart (not Shut Down) so that this change is saved. Make sure to have internet connection, so that when Windows starts it automatically gets and installs new driver for GPU card. 

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Oh I know nothing of the modded driver I read some things about it but I'm confused...

Thanks for the replies guys will try tomorrow see if anything works for now I went back to 765 don't wanna burn the 980 just got it haha

Yeah I'll write up a little guide for you but messing around with BIOS' can be problematic if something goes wrong so it's up to you. 

How did you install the driver for the 980M? Installing directly from Nvidia should result in a No Compatible Hardware error unless the .inf is modified. 

I believe this Clevo one should work but untested by me

https://www.techpowerup.com/vgabios/208218/208218

There were threads on NotebookReview about this issue but the site was closed down at the end of January so a lot of information is now harder to find.

The Alienware 18 was released with dual 980M's and each card had to have a different vBIOS for the systems fan control. If your 980M was removed from the secondary slot of the 18 then it will have a vBIOS that isn't compatible with your laptop. This is often the issue when people go to use a 980M in another machine. The 'New' cards that are selling out of China aren't new, they are pretty much all stripped from old laptops. 

You could try this vBIOS version but if that also doesn't work then you may have to try a few others.

https://www.techpowerup.com/vgabios/197754/197754

If you wanted to try the driver first then that may be a good way to start. Make sure you use DDU to completely remove any traces of the old driver before trying to install a new one. I'm assuming you got the modded driver for the 980M from someone or learned how to mod it yourself?

Flash a vBIOS at your own risk though. If you don't know how to flash an Nvidia vBIOS then let me know and I'll walk you through it. 

I really really appreciate your help! If only somehow I could repay answering to a random guy whimpering. Thanks...

cannot find anything that looks like a dedicated gpu fan driver though any hints?

Yeah I know they aren't new. I also had issues with the drivers kinda depressing. About the vbios I watched some videos of jayztwocents but if you are not bored I'd like a guide concentrated so tomorrow morning I'll try everything. Today all day I was messing around and searching all the internet to no avail.really exhausted. Thank you very much for responding. Greetings from Greece

Don't have a choice anyways I can't use it as I t is and refunding won't actually give me anything I guess... So I just ddu safe mode and then tried the manually downloaded 511.xx driver latest for 980m according to Nvidia but like you said got error so I just got the one from windows update. Then I downloaded a driver update software driver booster I believe. The card works but can't run anything or volcano erupts haha if only the fan was working

There are a few drivers out there that work with the Windows update but they are pretty old. 

First thing is to get the fan working and then I can help you through the driver situation.

The vBIOS controls the system fan control

It's no problem at all. Always happy to help. 

If you have the 120hz display then the laptop always runs off the dedicated card so flashing the vBIOS is a little tricky as the card will start heating up straight away. This is much easier to do with the 60Hz display that uses Optimus. You may want to do most of the prep work with your old card installed. 

Flashing an NVidia vBIOS - Do at your own risk

- Download NVFlash 

https://www.techpowerup.com/download/nvidia-nvflash/

- Create a folder called nvflash in your C: drive (where you have the Program Files, Program Files (x86), Users, etc folders)

- Extract the files from the nvflash download and put them all into the new nvflash folder that you made. The files are a little different between versions of NVFlash. To extract the files just right click on the downloaded file and there should be an option to Extract. Browse for your new nvflash folder. 

You should have some or all of the following files or even something slightly different. If yours has nvflash64.exe then you'll need to know this for later. 

nvflash.exe

nvflsh32.sys

nvflsh64.sys

- Download the BIOS version from TechPowerUp and place this file in the nvflash folder with the other files. Write down the 6 digit number of the BIOS for later

This is where you will have to insert your 980M. I also prefer to disable any network so no random updates mess everything up. 

- Use GPU-Z to save your old vBIOS. There will be an option to save next to the current vBIOS version

- Open Device Manager and disable the 980M

- Type CMD into the Start menu, right click it and run as administrator

- Type cd C:\nvflash then press enter. (if you had nvflash64.exe then you'll have to write this instead of just nvflash

- Type nvflash -6 ROM_NAME.rom (ROM_NAME is the 6 digit number from earlier) and press enter

- The flash will start after you press y a few times to accept it

- If the flash is successful then go back into Device Manager and enable the card and restart the laptop.

- If something goes wrong during the flash then DO NOT shut down your laptop. Keep trying to flash until it works. 

Hopefully this fixes your fan control issue. There is always a chance that the card itself has an issue.