If you run benchmarks against a SATA 2 hard drive then hobble it to SATA 1 with the jumper (yes, it's connected to a SATA 2 controller) you find hardly any difference in the results.
For the amount of money and lost time you would never make that up in a speedier hard drive.
My advice is to replace your existing drive with a lower seek time hard drive. Let's say your current drive is a common 8 mS (milliSecond) seek drive or 5400 RPM. Pushing the seek time to 4 or less mS or swapping for a 7200 RPM or even that 10K or 15K RPM drive will help more than a move to SATA 2 or 3.
Bob
I would like to retrofit my older HP pavilion with faster hard drives. I am a little confused by what I need. So:
1. I presume I need a new hard drive controller. The ones I have looked at on the net all seem to be some sort of RAID controllers. Will these devices support one or two hard drives NOT working in tandem?
2. What about my motherboard? It has built in sata I plugins. Apparently the new controller would use a pci slot. Will the motherboard take advantage of the speed increase of sata II or III with the controller going in a pci slot?
3. Any recommendations on a 2 port controller (low to mid range)?

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