This is what four SCSI hard-drives can do for you in a RAID-0 configuration.  All four are 15k RPM Seagate Cheetah's.  Two are generation 3, and the other two are generation 4. I'm using a ATTO's UL5D adapter, which is PCI-Express bus, dual-channel.  I'm running two drives on each channel.

But the real magic lies in a special piece of stripping software that ATTO makes, or used to make.  It's very hard to find anymore.  Originally just called "Raid Striping", it got renamed to "Express Power Center" and the price actually went up (cringe).  It was hard to shell out $300 for old software that no one uses.  Even more suprising was the small CD it came on: 1.4 MB including the HTML manual.  Yes, the magic is in driver buried in an msi files that takes up a mere 273KB. That's where your $300 went. 

Another odd thing is that you use this software to create the "stripe group".  But once you've made it, all the information must be on the drives themselves.  If you re-install the O/S, you will not have to re-install PowerCenter.  The stripe group will be recognized by the UL5d (or course you ahve to reinstall the UL5D drivers, explained below).  I'm surprised the PowerCenter drivers do not need to be re-installed, because it was my understanding that the reason they were so fast is that, unlikely most pure hardware based RAID solutions, it used a software interface with the O/S to highly optimize read/writes. 

Well, however it works, the results are pretty amazing.  250MB/sec is just unbelieveable throughput.  I do have an extra UL5D, and a motherboard with an extra PCI Express slot, but I doubt running all 4 drives on separate SCSI channels would yield any better performance.   The bottle neck is not the channels, it's the hard-drives themselves, which top out at about 70MB each.  Now if I had another 4 drives, yes running pairs of them on separate channels would keep the channels from being bottle necks.  So maybe I could get something close to 500MB/sec.  But I'm content with 250MB. :-)

To install the UL5D drivers for an existing Windows Installation

	go to the "v211" folder and run set-up.  

	go to compmgmt.msc - Devices

	You should see two sevices called "SCSI".  Uninstall them.

	Reboot.

	Windows will detect them.  Found New Hardware appears.

	Browse to "v211" folder

	Will recognize them as ATTO UL5D devices.