I'm assuming you're using a P55 motherboard with a Marvel SATA III controller from this threaD?
»Want to go with a SSD now...
Vertex 2's are SATA II drives only capable of 3.0 Gbps. As Koitsu said, you may need to "force" the drive to SATA II, as it seems to be running at SATA I speeds right now. I can't help you here, my Vertex 2 120GB ran natively at SATA II speeds when I installed it, so I never looked into it.
It also looks like you got two different versions of the Vertex 2--one with 34/32nm NAND, and one with 25nm NAND flash. See here for more information: »www.tomshardware.com/reviews/ocz···867.html
I'm not a HDD guy, so I'll let Koitsu guide you through the troubleshooting, but booting off RAID 0 is a Very Bad idea as it doubles the chance of failure--booting off of an SSD raid is an even worse idea (SSDs tend to fail suddenly and with no warning), and running SSDs outside of Ivy Bridge LGA1155 7-series motherboards (ONLY) where TRIM is supported
is an even worse idea.
I'm baffled why you would pick up two smaller SATA II--you seem to be going for maximum amount of problems with this approach.
Why not just get a Samsung 250GB 840 Series 2.5" Solid State Drive
for $170? Set your SATA controller to AHCI mode and call it a day.--
Those who would give up Essential Liberty to purchase a little Temporary Safety, deserve neither Liberty nor Safety.