SATA 150 is technically UDMA 7. The BIOS is going to identify the UDMA mode of every SATA drive as UDMA 5. Do not worry, this is normal. There is nothing you can do about it.
Hhmmm...I have a new Seagate Barracuda SATA 3.0 in one machine and a Hitachi SATA 3.0 in another and bios ID's them both as UDMA 6. Now, on both these builds I did NOT attempt to install any drivers beofre installing Windows and everything seemed to work OK. BTW...the Seagate is VERY quiet...no weird clicking noises.
However, they both benchmark as a drive index 76 MB/s and I have an older, ATA drive that benches at 67 MB/s in Sisoft.