Internet Doesn't Work Properly?

The electric went off in my house about an hour ago, causing my computer to turn off as a result. Ever since, the internet on my PC has been acting up.

My internet was working perfectly before the power cut both on my laptop (my mum was using it at the time) and PC, however, while I've got no problems with the internet on the laptop, my PC keeps losing the connection to a ridiculous degree. It'll drop the connection for over a minute at a time, come back on literally long enough for me to refresh/load 1 webpage (~5 seconds), then go back off again for another minute or two.

All the lights on the router are on and I've even cross-referenced (lacking a better term...) the internet connection between my lap top and desk top and my laptop will work fine when my PC is telling me there's no connection and nothing will load on it. It seems to me that something has happened to my desktop when the power went out but I have no idea where to begin to even try to find out what's wrong.

I've tried turning off the router by both the wall and the little button on the back of it, and I've restarted my PC twice as well and still the internet doesn't work properly. My laptop picked up the connection as soon as the router came back on with no problem but my desktop struggled to find the connection and only picked it up after turning the router off twice aand restarting the computer twice as well and as I said, when it finally did find the connection it just keeps dropping it.