My internet doesn't work properly on my Desktop Computer however is fine on my laptop?

[skinnyindiv]

So only recently my TP-Link Modem has been playing up on my desktop computer. I am upstairs and the modem is downstairs, however, it always says "No internet" when I connect and when I troubleshoot it tells me to restart the modem, which I have done multiple times. On my laptop though, everything runs fine and my internet is working as it should. When the internet does briefly work (only for about 20 mins) I find myself with 400 pings with the games I play on my desktop. My download speed on my desktop, when it works, is around 200 kilobytes a second. On my laptop, however, it is 3 MBS per second. My Wifi card in my desktop computer is a Qualcomm Atheros AR9485 Wireless Network Adapter. Any help would be appreciated!

 

[Lutfij]

The following are suggestions for your desktop:
1| Make sure you're on the latest BIOS update for your desktop's motherboard.
2| Make sure you're on the latest drivers for your wireless/wired adapter.
3| Speaking of wireless adapter, there are known issues with Qualcomm/Atheros/Broadcomm/Killer networking cards. You can try installing them in an elevated command,
Right click installer>Run as Administrator

Do you have a link to your adapter?

4| You may also want to share your full system's specs like so:
CPU:
Motherboard:
Ram:
SSD/HDD:
GPU:
PSU:
Chassis:
OS:

 

[skinnyindiv]

Sorry, this may be obvious but what do I do with the WinRAR for my Wireless Network Adapter after I have downloaded it? I thought it may have fixed my internet at first cause it came on straight away after I downloaded it but now my internet is back to where it started.
And what do you mean by installing "them" in your third tip? Sorry, again it may be obvious but If I could get a link or directions for that it would be great!
Updated my motherboard to the latest BIOS update, didn't change much.