I am in the market for a new motherboard because my oldie quit on me.
I am startled to discover that all new motherboards on the market seem
to have only one IDE header, allowing for only two PATA hard drives.
I want to continue using my older PATA hard drives, and I want to be
able to boot from them selectively as I do now. I use the dual-boot
technique allowed for in the boot.ini file. Yes, I am running XP.
I've been told one cannot boot from IDE Extender cards. I don't know
if one can boot from a PATA drive connected to a SATA header via an
adapter, but I have been told probably not.
I'd rather not buy four new hard drives. Anyone have any advice?
Thanks
Duke
The BIOS uses something called (extended) INT 0x13 for boot
support on separate controller cards. If you want to boot
from a separate two port IDE card, then the card needs its
own BIOS chip. The BIOS chip contains the INT 0x13 code.
The main BIOS detects the card during POST, and loads
the BIOS from the card. And that is how it figures out
how to boot. This even works for separately plugged in
RAID cards.
http://en.wikipedia.org/wiki/INT_13
As long as the card you add, has the BIOS chip on it,
and "INT 19 capture" is enabled in the motherboard BIOS
setup screen, the motherboard should be able to support
booting from it. Sometimes, it make take a few minutes, to
figure out what the item is that you want to enable, to boot
from it. (19 is the decimal equivalent of hexidecimal 0x13,
and the BIOS writers are a bit dopey to break convention.
If two BIOS writers were talking to one another, they'd
certainly refer to it using 0x13. Putting 19 on the
BIOS screen is a disservice.)
I have three Promise IDE cards here, and boot from them
regularly.
On this card, the BIOS version is printed on a label
stuck to the chip. It implies the main chip is an
IDE controller, and also contains some BIOS code in
internal memory. (I'm not aware of a datasheet
being available for that chip, and some details
about it would be interesting.)
http://c1.neweggimages.com/NeweggImage/productimage/16-102-007-03.jpg
On this card, you can see the BIOS chip on the left of
the picture. This is more typical of storage controllers.
http://c1.neweggimages.com/NeweggImage/productimage/15-158-081-03.jpg
The BIOS chip on some cards is flashable. Some of the
SATA add-in cards, allow changing them from "vanilla SATA"
to RAID controllers, by changing the contents of the BIOS
chip. That would include a different set of 0x13 routines.
So for some types of controller cards, you get to learn
about flashing them, soon after buying them. I wouldn't
expect that to be necessary with the IDE card you're about
to buy.
This is one of the older IDE controllers which is still
for sale. This one is based on SIL0680 (originally made
by CMD, but Silicon Image bought CMD and spruced up the
chip design that is still offered today). The BIOS chip
on this one, has the blue dot on it.
http://c1.neweggimages.com/NeweggImage/productimage/16-124-001-03.jpg
If you read the advertising for a product, and it
says explcitiy "will not boot", then you know that
function is broken. If the booting function is
broken, the card can still be used for "data" drives.
All it takes is the installation of the OS driver, and
then the card will be accessible through the OS.
Paul