|The D865GBF mboard supports the original SATA a.k.a. SATA I specs - max burst data transfer speed 150mbytes/sec = 1.5gbits/sec.|
NOTE that hard drives cannot run at their max burst data transfer speed all the time. How long they can run at that speed in one continuous "go" is determined by the size of the ram cache the drive has on it's board - at most it can only do that for a couple of minutes, then the drive reverts to it's max continuous data transfer speed, at best, which is much slower - I don't know of any conventional drive that has a max continuous data transfer speed faster than 100mbytes/sec or so (solid state hard SATA III drives probably have a faster rate).
Most recent and new SATA hard drives support SATA II a.k.a. SATA 2 specs - max burst data transfer speed 300mbytes/sec = 3.0gbits/sec.
A few new SATA hard drives support SATA III a.k.a. SATA 3.0 specs - but they cost a lot more for the same size of drive - max burst data transfer speed 600mbytes/sec = 6.0gbits/sec.
(SATA drives transfer data at 10 bits per byte, not 8)
Some mboard chipsets that support only the original SATA specs will recognize a SATA II or a SATA III drive anyway, but can only run it at the original SATA specs - max burst data transfer speed 150mbytes/sec = 1.5gbits/sec.
However, other mboard chipsets that support only the original SATA specs WILL NOT RECOGNIZE a SATA II or a SATA III drive at all, unless the drive has pins on it a jumper can be installed on to limit the drive to the original SATA specs - 150mbytes/sec = 1.5gbits/sec. Some drive models have the pins for that, some don't. E.g. Seagate 500gb SATA II desktop drives I have bought have the pins and the jumper is already installed - you remove the jumper to have the drive be able to reach it's full burst speed - 300mbytes/sec = 3.0gbits/sec.
If you buy yourself a PCI or PCI-E X1 SATA II drive controller card and install it, that will support the SATA II specs of any SATA II or SATA III hard drive connected to the card. However, if you want to boot an operating system from a partition on the drive connected to the card, you must set the Boot Order or similar settings in the bios Setup such that SCSI is listed before any hard drive. When you install an operating system on a drive connected to the drive controller card, you must load drivers for the card's SATA controller chipset while installing the operating system, early in the loading of the files from the CD or DVD.
I haven't noticed whether there are any PCI or PCI-E X1 SATA III drive controller cards available - if they are available there's probably not many of them to choose from.
If you get a PCI drive controller card, usually it cannot work properly if it's in the last PCI slot of the PCI slots closest to the center of the mboard - that slot is usually forced to use the same IRQ as the video and it's likely only PCI video cards will work properly when installed in that slot. The info about which PCI slot shares an IRQ with what is usually stated in the mboard manual.