Yeouch! That's no small feat! Keep in mind that you aren't just
going to need to worry about the hard drives, but also getting the
data to and from somewhere useful! That probably means some pretty
specialized video equipment (though I'm guessing you already know
about that part!) and probably some pretty beefy LAN.
Definitely not.
Other solutions do exist, but they are not cheap. Basically you would
be looking at some form of Network Attached Storage setup, though
depending on your application that might be totally pointless.
If you plan on keeping costs semi-reasonable (ie no SCSI) then the
Raptor 150/Raptor X is pretty much the only drive that will fit the
bill for you. 4 of those should indeed do the trick, and I'm quite
certain that you're going to want the extra 50MB/s+ worth of
theoretical headroom.
Well now, here is where things get tricky. I really don't know how
these chipsets would perform because I've never had the need (or
budget!) to aim for such targets. However I wouldn't be counting on
them being up to the task. These are desktop chipsets and you're
looking at very much a workstation/server style application. I would
give it maybe a 50/50 shot of working reliably at your required
bandwidth.
What you might want to do is to buy the systems with a nForce chipset
and try it out. However in buying the system make sure that it has a
free PCI-Express 4x slot so that you can drop a full-fledged RAID
add-in card, something like a 3Ware 9590:
http://www.3ware.com/products/serial_ata2-9590.asp
Newegg lists the 8-port version of this card at just over $500:
http://www.newegg.com/Product/Product.asp?Item=N82E16816116037
Note that you might want to consider the possibility of expanding to 6
or 8 drives in your array if 4 won't cut it.
A few other points of note, many of which you are probably well aware
of already, but others might be new:
1. You'll almost certainly want a dual-core processor (if not 4
cores). This data streaming on it's own is going to be enough to
swamp a fairly capable single core. With only a single-core chip any
other tasks (programs, OS, whatever) are going to start eating into
your performance. A dual-core chip should go a long way to keeping
things running smoothly.
2. Enough memory that you basically won't ever need to worry about
paging out your OS or applications.
3. Spend some time tweaking the software for maximum throughput. You
can probably do away with a lot of the logging and system recovery
functionality in favor of pure performance. Also things like larger
than default cluster sizes are likely to be helpful. You might find a
few guides out there that can give you some suggestions, but a bit of
trial and error is likely to be necessary to really get things working
well.
4. You are obviously going to need a hefty computer case and power
supply. You're looking at a minimum of 5 hard drives (1 boot drive
and 4 for your array) and maybe more like 8 drives. Obviously your
plain-jane desktop case isn't going to cut it here. Similarly a 500W
power supply is probably the minimum you're going to want here.
5. Be sure that your case has lots of airflow. At the very least
you're going to have 4 drives spitting out a fair chunk of heat along
with one fairly high-end processor. And whatever you're using to take
data in and spit it out again are also going to be some high-end
parts. All in all, that's a LOT of heat being generated in a case,
even if it is going to be a pretty large case. Now SATA is a godsend
here when compared to PATA, since you'll have MUCH less ribbon cable
cluttering up your case, but you'll still need to make sure that the
cables stay neatly tied up and you've got fans sucking and blowing air
effectively throughout the case.
