A little follow-up:
I just completed a test with the following system, stock settings in all cases:
ASRock G41M-S3 motherboard
Intel 3.2 GHz Pentium 4 model 640
2 x 2GB Corsair XMS3 DDR3-1333 memory (4GB total, dual channel)
used Highpoint RocketRAID 2322 PCI-E x4 RAID controller w/ original driver
2 x brand new WD2003ABYX HDDs in RAID 0 (purchased from Newegg)
ATTO Disk Benchmark v2.46
Here’s a screen shot of the ATTO results:
http://www.supremelaw.org/systems/wd/2xWD2503ABYX.RAID-0.RR2322.G41M-S3.JPG
Max observed READ speed is 296.2 MB per second.
This rate is just a fraction short of the SATA-II bandwidth of 300 MB/second
i.e. this READ speed is slightly better than what is being observed with
the best single 3G SSD, regardless of vendors.
Total cost of the 2 x WD2503ABYX at Newegg: 2 x $70 = $140
(PCI-E controller for either the x1 slot or x16 slot is a separate cost item)
Bear in mind, we used the only x16 PCI-E slot for this experiment:
for this type of machine, we would be more than happy to
upgrade the on-board video with any of a number of excellent
x1 PCI-E video cards that are now available, from different vendors.
Because the ASRock G41M-S3 also has 2 x legacy PCI slots, one of those
can be easily assigned to a Gigabit Network card: 32 bits @ 33 MHz
= 1,056 Mbps. which is just enough bandwidth for a single Gigabit NIC.
We did this experiment because the total cost of this DIY system
is very reasonable, particularly for SOHO settings which need
a reliable backup storage server, preferably with a Gigabit LAN.
Our next experiment will be to upgrade the RAID controller to
a Highpoint RocketRAID 2720SGL, and install Windows 7
to the same 2 x WD2503ABYX HDDs wired to that 2720SGL.
We’re hoping it will exceed the 300 MB/second threshold
with the faster controller and more recent driver for Windows 7.
Stay tuned: we should have more to report in about 2 weeks 
MRFS
