Since it was intermittent, what's to tell us the card is good? I continue to just issue some USB WiFI since repair is costly.
I see you tried all the machine drivers so my thought is you need a way to test this card in this machine.
Linux?
I recently had a problem with a failing SSD drive. After replacing the drive and doing a clean installation of Windows 8.1, the computer works fine. Except, I seem to have problems with my network card. There's no wifi connectivity, and the network card does not even show up in Device Manager. (See Screenshot) . I have never had problems with this before, so it's clearly related to either the new hard drive or the clean installation of windows.
My laptop is an MSI GS70 2QE, the wireless card is a Killer Wireless -m/a/ac 1525, see more detailed System info here.
The wifi did work twice even after the clean installation ,see screenshot here showing device manager at a time when it worked. First, it started to work after updating the chipset drivers I think, the second time it was hard to localise why it started working since I tried so many different things before reboot. The thing is, both of these times, the wifi was working without any problems whatsoever for a long time, but as soon as I put my computer to sleep the network card was disabled again.
What I've tried so far:
- Reinstalling the drivers, but unsurprisingly that didn't help since it doesn't even recognize the laptop card. I also performed a driver scan with DriverTalent and Intel utility and updated the missing ones,
- Since I recently opened up the case to insert the new SSD, I might have acidentally done something with the network card as well. However, the SSD-installing was so fast and easy, so I doubt it, and when I opened up my computer to check, the network card seems to be stable and fastened with a screw (see picture).
- As far as I know, my laptop does not have a hotkey for switching on/off wi-fi(see keyboard layout), but I've tried Fn+F8 since I know other MSi-models have that hotkey.
I really don't know what to do at this point, so if anyone has any suggestions I would appreciate it a lot.

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