SATA revision 1.0 - 1.5 Gbit/s - 150 MB/s
SATA revision 2.0 - 3 Gbit/s - 300 MB/s
SATA revision 3.0 - 6 Gbit/s - 600 MB/s
The bus can handle 2 Devices at Sata 2.0 Speed.
Pentium D high end versions top out at 8.5 GB Single Core and Slower Versions do less.
You won't get 6GB speed thru the PCI Bus and at the same time get 8GB thru the X16 video slot AND have anything else run. Overtaxing the PCI bus causes slowdowns, lockups and otherwise video and audio artifiacts since the video and audio also run on the PCI Bus. One way around this is to use PCI-E video HDMI Audio which keeps the audio on the X16 bus via an HDMI Monitor.
