I have recently formatted my computer, I have also rendered a clip using wmv codec, x264 codec[vdub] and h264 codec.

Each time I render, the quality is very lossy, even when I use settings I have used for over a year now.

What could be a factor to the bad render quality I am receiving?

The uncompressed version is perfectly clear, like normal.
No matter what bitrate I use or what settings, it turn out the same in every version, lots of artifacting/blurriness around the entire clip.

I know how to render perfect quality, but all of a sudden it just gives up on me.

Here is an example :
Bad quality


Good quality