bringing my computer into the 21st century

[dsr at tao.merseine.nu]

On Thu, Jun 19, 2003 at 01:05:38PM -0400, Seth Gordon wrote:
> I have a P-II 350 MHz computer sitting in my office, and I want to spiff
> it up, within the limits of my budget, before everything that's
> compatible with its motherboard becomes "legacy hardware".
> 
> In particular, I want to put in a SCSI controller and a few drives, so I
> can set up a RAID system.  However, the prospect of going to
> pricewatch.com and just ordering a few refurbished drives is
> intimidating me, because:
> 
> (a) There appears to be an alphabet soup of competing SCSI versions, and
> I'm not sure in advance what drives are compatible with what
> controllers.
> 
> (b) My motherboard only has a 100 MHz bus, and I don't want to waste
> money on drives that are pumping out data faster than the bus can
> handle.

SCSI comes in a few flavors, but the significant ones are:

Narrow -- old 8-bit wide bus
Wide   -- 16-bit wide bus
Fast   -- 10MB/s on narrow, 20MB/s on wide
Ultra (Fast 20) -- 20MB/s on narrow, 40MB/s on wide
Ultra2 (Fast 40) -- 40MB/s, 80MB/s -- requires LVD (low voltage
differential) drives
Ultra3 (Ultra160) -- 160MB/s on wide bus, requires LVD, allows long
cables.
Ultra4 (Ultra320) -- 320MB/s.

A cheap SCSI card (under $100) will be Ultra Wide or possibly Ultra2.
You can get a brand name Ultra160 for $250, or an Ultra320 for $300ish.

Refurb'd Seagate U160 drives, 18GB each, are about $160 each.

So, for a nice little 5 drive RAID (striping, parity, one spare) you
would spend $250 + (5 x 160) = $1050 and have a little less than 80 GB
of nice, fast, reliable storage.

In contrast:

A 3Ware 7500-4 ATA RAID controller runs $260 or so, and 4 80GB Maxtors
run $100 each. So, for $660, you can have all-new, very fast, quite
reliable storage to the tune of 240GB.

And if you are willing to do software RAID, you could use a channel of
your onboard IDE and a $30 2-channel PCI IDE controller and put 6 80GB
drives, yielding a not-quite-so-fast but still quite capable 400GB of
reliable storage for $600.

-dsr-

-- 
Network engineer / pre-sales engineer available in the Boston area.
http://tao.merseine.nu/~dsr