I recently upgraded my Windows XP (!) computer to a single Crucial M4 SSD. The system is running very fast and without problem, but running HD Tune Pro (and CrystalDisk) revealed that sequential read rate is only 80MB/s (with a block size of 64K) and write is 60MB/s. Also, IOPS is only 6,000 (for 4KB). This too seems very low.
There are two SATA controllers (why?) on the motherboard: Promise and VIA. The spec ( http://www.asus.com/Motherboards/AMD_Socket_939/A8V_Deluxe/#specifications ) suggests that the Promise controller (which I am currently using) could be limited to SATA 1.5. However, if that were the case then the transfer rate should be much higher, I think. 1.5 Gb/s = 187.5 MB/s. Also, why is the IOPS so low? (6,000 * 4KB = 24MB).
Research on the internet suggests the performance should be over 400MB/s, so the drive should be much faster.
Currently using the Promise SATA port. I tried plugging the SSD into the VIA SATA port on the motherboard, but I get a bios error "No BIOS is installed." and it will not boot. It's strange because when there is no hard drive installed I get "No hard drives found."
I installed the Promise 378 drivers during the Windows install.
Do you think there is a problem with Windows XP, or perhaps the drivers? Could the motherboard be set up for RAID? I tried changing the settings, but it didn't help.