Annoying internet performance

Hi everyone

I'm having some really annoying problems with my internet/wireless adapter.

I've tried everything, even to the point of re-installing windows7 (several times), trying old drivers, new drivers, different firewalls, no firewalls, and still no improvement.

My internet performance when I first turn my computer on is fine, but after about 2 minutes of browsing or anything it drops completely, to about 10Kbps.

I know it's just my computer as all other computers in the house don't have this problem.

Diagnosing the wireless connection with Windows Network Diagnostics finds a "Problem with wireless adapter or access point". It says it's fixed (it resets the wireless adapter), and after this everything is fine for about 2-5 minutes, things can download at upto 1Mbps (could be MBps not sure), but then drops back to near nothing.

My wireless adapter is a TP-Link WN851N v2.

Thanks in advance to anyone who can help!

A little but our computers are never left on downloading things. This problem happens all the time, even when no other computers are on. If I need something quickly I have to use a flatmates computer because mine will take forever to download or load a page.

I use Comodo Antivirus and Firewall. I've tried at different defense setting levels, I've even tried without using a Firewall at all (well except for the Windows one), still no solution.

about 1 hr ago. I reinstalled windows earlier today, and only connected to the internet after installing the programs that I use. As soon as my antivirus signature database was updated I ran a scan, and with windows defender also, still nothing.

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