More of a question than an issue. Most sata ports are "paired" is my understanding. Meaning 2 run through the same circuit on the MB. Is my understanding correct? I have been successful setting up raid several times on motherboards using the built in raid mode. I noticed a non raid drive performing slowly on 1 board and switched it around to another set of ports- switched the cable with a DVD drive cable. Rebooted and drive was back to normal. Still wondering about this phrase I see (or something similar) in the MB installation manuals. I am just stupid because googling it receives no hits whit the specific phrase except for PDF installation manuals. I don't understand what this means..." If you set this item to RAID mode, it is suggested to install SATA ODD driver on SATA3_4 or SATA3_5 port" What is a SATA ODD driver??
PATA (IDE) ran in Parallel and you could set a jumper for Master & Slave. Sata is Serial ATA & are independant. The onboard Raid is a Software Raid. If it's an Intel based motherboard then the INTEL RST rom is used to setup the raid & you should also use the driver. So Sata3_0 to Sata3_3 are probably running on an Intel controller. SATA3_4 or SATA3_5 port's are probably some other controller, ie ASMEDIA or Marvel. To see your ODD (Optical drive) you would need to load the controller drivers.
On some older amd motherboards with 6 sata ports only the first 4 connectors are seen by the system in IDE mode, you need to have AHCI enabled to see ports 5 and 6.
They are all AsRock AMD boards. I know, I know. Considered bad boards but out of about 30 boards in the last 20+ years only one has lost its ethernet and another it sound (fixed with PCI cards). Mild overclocks (and core unlocks on most) and all are still going to date. The one in question has 6 SATA ports. No split drivers (or the 4 sata 2, 2 sata 3 bs). Question answered - Thanks Joe C. Somewhat obvious so I feel a DUH moment. Explains why the HDD performed back to standard after switching cables around - just dumb luck on my part. 2 raided drives, 2 unraided drives and 2 DVD drive (1 is blue ray). Many thanks. This is why I still love MDL.