I just purchased a Dimension 9100 with the 820D setup, 1 Gig of DDR2 memory, 160 HD, and 256Meg X600 video card.  I thought this would be a fast setup, but it is actually slow.  VERY slow compared to my homebuilt Athlon 2800+ with 512Meg of PC2700 memory, and a smallish ATI 9600 AIW with only 128Meg.

 

As it stands I cannot find anything in the setup or configuration that suggests changes that might be helpful.  Its main use is for gaming, but it is less than 5 days old and is currently destined to a life of being unused.