R9 270 slower than 9800GT - new card in legacy system

[Paratus]

If you want to troubleshoot, can you overclock the X2. If the performance increase is linear the you are horribly CPU bound.

 

[Blue_Max]

Boy, this reminds me of ~14 years ago when I went from an nVidia TNT card to a Voodoo5 and saw no speed improvement because I was held back by my Celeron300A@450... I needed more CPU power to push the video card into its potential.

 

[2is]

If you want to troubleshoot, can you overclock the X2. If the performance increase is linear the you are horribly CPU bound.

Obvious problem is obvious. No need to troubleshoot unless you're bored an have nothing better to do.