I have an ASUS mainbord (A7V333) with two IDE controller on board (one
normal and a one PROMISE for RAID).
So, there are 4 independent IDE channels: is it possible to put 4 IDE
devices(HD1, HD2, DVD player, DVD-RW), each one on a separate channel?
Yes
Actually the HD1 and HD2 are on the primary IDE channel and the the DVDs
on the second IDE channel, while the PROMISE controller is disabled.
That'll work too. If you won't be doing a lot of
time-critical copying between one HDD to the other, or from
one optical to the other, your current setup should suffice.
For example, burning DVDs from data on the HDDs should be
fine since the HDDs are on a different IDE channel. One
exception would be if the data were on the primary OS drive
while you're trying to otherwise use the system (there's no
"fix" for that other than putting the data elsewhere), or to
a lesser extent, having the data on the other HDD (while
still using PC, accessing primary OS drive) since they're on
same IDE channel. If you don't ever encounter problems
using system as-configured, I'd leave it like that.
The idea is to put the 4 devices each one as master on each channel in
order to get the best performance.
But will the Promise controller work just as an additional IDE
controller or only as a RAID controller?
I've had two A7V333 motherboards, still have one here but
it's dead... was sold to someone who did "something" to it
then returned it (think mishandling scrambled the EEPROM but
I haven't had a chance to diagnose it yet).
You can attach devices to the Promise controller but it's
not as fast. The chipset-integral IDE "main" controller
isn't on the PCI bus, and the Via KT266/333/400 (and 600?)
chipsets had relatively poor PCI performance, so while any
motherboard might take a performance hit by having a drive
controller on the PCI bus, it's even more evident on these
Via chipsets.
Even so, in certain situations there might be benefit to
putting each drive on a separate channel. Since the Promise
controller will not have similar performance, you'd not want
the (a single) OS drive running from it. If you're doing
anything demanding in realtime from the 2nd drive, you'd not
want it on the Promise controller either. Don't get me
wrong, if you had the 2nd HDD on the Promise controller it'd
have fast enough transfer for burning DVDs, but unless you'd
be heavily using the other/OS drive simultaneously you might
find it's still slower than leaving the 2nd drive on the
primary chipset controller.
If you want to use any non-HDD (ATAPI, like the optical DVD
drives) on the promise controller, you'll need a modified
motherboard bios. Basically the modded motherboard bios is
modular (as the unmodded bios is), such that the Promise
controller bios module can be "swapped out" and a Promise
UATA bios inserted in it's place. That is necessary,
manditory to use the atapi devices. Naturally you won't get
these modded bios from Asus, if you're comfortable modifying
a bios then you could make your own, otherwise there are
pre-modified bios available. Here is one source:
http://web21.p15131386.pureserver.info/index.php?cid=2
Of those listed, the "UDMA (nnnn=base bios version per Asus
naming scheme)" allows use of ATAPI (DVD drives) but you can
no longer RAID any HDDs, it becomes a "normal" non-RAID IDE
controller. The "Full RAID (nnnn)" replaces the Promise
"Lite" Raid bios with the full Promise Bios. Basically it
was cheaper for motherboard manufacturers to license the
"lite" raid bios, but the ability to have full Promise RAID
function is possible, because it's the exact same Promise
chipset... all you need to unlock those functions is the
"Full" raid bios. offhand I don't recall the exact features
added, a Google search should detail this.
Then there's the "UDMA/fastboot (nnnn)" bios, which removes
ability to RAID the HDDs, allows ATAPI. It differs from the
"UDMA" bios in that the drives aren't detected at POST, so
the boot process is faster but you can't use the drives to
boot, and have NO access to them until after the Windows'
Promise driver is loaded. Unless you're always in a hurry
to boot and want to shave 5 seconds off of your boot time,
there's no other reason to chose the "fastboot" bios.
If you flash the modded bios you can still just disable the
Promise controller via the motherboard jumper or disable in
Windows Device Manager, except for the aspects I mentioned
dealing with it remains unchanged except that with the UDMA
bios(es) you need use the appropriate "UDMA driver
(nnnnnnnn)" or "Full RAID (nnnnnnn)" driver,
http://web21.p15131386.pureserver.info/?url=&cid=12
I tried both the UDMA and Full Raid drive on one of my
A7V333, ran the UDMA for almost a year... seemed fine.
Regardless of which bios and/or drive you use, if you enable
the Promise controller and use it for anything you might see
better performance by using the Via Latency Patch available
somehwere on the
http://www.viaarena.com 'site (I don't
remember the page/link).
Again, unless you find problems with your current
configuration you may find little benefit to using the
Promise controller. On the other hand I found it very
useful for adding additional HDDs, regardless of whether
they're RAIDed or not it does still allow single-drive
volumes.... with the lower performance it's not optimal but
still sufficient for archival or other
non-high-bitrate-dependant uses.
