Ok... there is no such south bridge/north bridge drivers. They are chipset drivers. The chipset of your board it VIA K8T890 north bridge + 8237 southbridge. The drivers for the chipset is the VIA 4in1. No special drivers are necessary if you connect the HDD to the connectors that are controlled by this chip:
"Supports 2-channel SATA RAID 0/1 by VT8237" Your manual should have a diagram that shows which connector belong to that chip. My bet, from a picture of your board, they are the 2 below the memory slots.
Now, the funny part.
2nd SATA RAID
- Supports 2-ch SATA RAID 0/1 by VIA VT6421 PCI controller
- Supports RAID 0/1/0+1
This controller looks like a RAID only controller. Usually, optical devices are not supported by PCI RAID controller. So, trying to connect your DVD to the lower IDE connector simply wont work. It has to be plugged to one of the 2 blue connector on the side. This controller, being a PCI controller usually need drivers to be used, either as SATA/IDE or RAID SATA/IDE. I guess that the 2 SATA connector between the 2 VIA chips and the black on below the last PCI slot are those that are controlled by this chip.
So, your setup should be : Both HDD connected to the connectors controlled by the southbridge (VIA 8237) and both optical connected to the BLUE connector. RAID should be disabled in BIOS for the native controller(VIA8237), unless you plan to RAID them. NO drivers will be necessary for Windows to recognize the HDD if not RAIDed. The chipset will make them recognized. But, IF you plan TO RAID them, then DRIVERS WILL BE NECESSARY for Windows to recognize the RAID controller.. which is no more a SATA controller. It is now a RAID controller using the SATA interface.
If you dont have other HDD, in BIOS, disable the secondary RAID controller, the VIA VT6421. This will speed up POST time, as this controller wont have to look for devices..
This controller will need drivers to to be recognized by Windows. Not because it is SATA or RAID... but because it is on the PCI bus. Just like a sound card will need driver, or modem.. well, anything plugged in a PCI slot, or mounted onboard that share the PCI bus need drivers. This is the case for Promise, Ite or SIL SATA/RAID controller too, when used by board.