Wireless Network Signal and Noise Randomly dropping and rising

About a year ago I bought the components for a pc. All components have been working amazing for the past year and recently my wireless network card, an Edimax EW-7128G, has gone from 94-100% signal strength and 70% noise level to a shifting 63-100% signal strength and 13% to 70% noise level. The noise level almost always lowers with signal strength. I've tried moving the router and wireless card around quite a bit but they all seem to do nothing (my current setup seems to work most of the time). The actual quality of the connection doesn't seem to be degraded but it seems to foreshadow a future problem.

My router is a DI-634M and has been perfect for over a year now as well, but the difference is that while the network card shows a loss in connection strength, my router reports 95-100% all the time. I've been going crazy over this for a week or two now and I've been wondering what other people's opinion on what the problem could be is. I used all channels and they do the same thing eventually and Channel 1 in my area isn't even being used by anybody other than me.

The only thing that has changed in the past couple months is my hard drive space going from about 50% left to 20%. I used this wireless connection extensively as a media network for streaming movies/series/etc. to my ps3 but I haven't even been doing that as of late. Does the signal strength just degrade over time? Is this some sort of bug? I also play Aion and WoW with latency of 140-165 all the time with wireless and I would like that to stay the same. Any help is appreciated.

Wireless Network Card: http://www.newegg.com/Product/Prod [...] 6833315041
Router: http://www.newegg.com/Product/Prod [...] 6833127173