"the CPU and the system became more or less unusable for other tasks. In our tests, the Intel Quick Sync technology proved to be superior and can result in differences of several minutes or even hours for larger projects. "
OC while its true CPU high profile 1080P etc encoding will take 100% of the available CPU cycles, you can OC set the x264/ffmpeg to set a lower priority to the "below normal" setting for the app and it will not then interfere with other normal apps runing in the background...
you makes your choice and if quality si your only choice then OC software x264/ffmpeg encoding is the only choice , Quick Sync is fine for people than cant see the difference between a fuzzy divX HD encode and a real quality high profile x264 encode OC....
just something to consider for the future reviews...
for instance try this line for a visually better quality wireless streamable smaller file output.
avconv.exe -threads 4 -i "infile.mkv" -f mp4 -vcodec libx264 -crf 18 -minrate 800k -maxrate 2500k -bufsize 2500k -refs 3 -preset slow -vprofile high -flags2 -bpyramid -wpredp 0 -strict experimental -acodec aac -ac 2 -ab 128k -vf yadif,gradfun,hqdn3d,unsharp "outfile.MP4"