Strange behaviour with buffered rendering

[JumperTwo]

hm,i guess 40-50% performance hit is a little bit too much,i don't think it's that heavy.i'd like to hear what Henrik thinks about this

edit : devices with multi core gpu (for example Samsung Galaxy S2 and Samsung Galaxy S3, with their Mali 400 Mp4 ) don't seem to be affected by this , maybe because the driver takes the upscaling work and it's overhead to a second gpu's core?