Intel PR440FX 'Providence' Dual Pentium Pro Mainboard

I received an email from George Wang at www.interwb.com. He has the rare vintage Powerleap PL-Pro/II adapters purchased brand new from Powerleap. He also has the hard to find 256MB EDO-ECC memory modules, plus complete PR440FX mainboards complete with onboard SCSI, LAN, and audio. If you are interested, please visit his website!

• Here is a mirror of Intel's support information for the PR440FX, including the manual and latest BIOS revision.
• Another PR440FX page, locally mirrored.
• Linux information
• IRQ sharing information
• Here is a direct link to the 1.09 BIOS for the PR440FX, which is the last revision Intel released.
• This board *DOES* support PPro CPUs with 1MB of L2 cache. Right now I have a system with dual PPro 200MHz 1MB, running at 70MHz x 3.5 (240MHz) with a pair of Coolerguys heatsink/fan combos, and with a Micron 256MB EDO ECC Buffered memory stick running at 50ns. The system performs admirably under Linux 2.4.x. The board auto-detects the presence of a second CPU, so no need to set jumpers.
• You need a 5V VRM module for this board. 12V modules, or "dual" 5/12V modules will not do. Yes, straight 5V modules are expensive. No, there's nothing you can do about it. Protect the box with a good surge suppressor to help ensure that the VRM (about a $40 investment) doesn't get fried (happened to me), much less the rest of the board with it.

The jumpers on this board confused the hell out of me. So I will outline what they do here, and show you what combinations of clock/bus are possible. Intel's documentation is not always correct regarding the jumpers on this board.

To sum up quickly, if you want to run a CPU at 200MHz, EFGH jumpers must all be down (towards the edge of the board).

• The "E" and "F" jumpers on the board control the bus speed. You can set 50MHz, 60MHz, and 66MHz bus speeds at least. "F" is up for 60MHz and down for 66MHz, when "E" is in the down position.
• The "G" and "H" jumpers on the board control the CPU speed multiplier. The following is a posting from the FreeBSD mailing list outlining the multiplier jumper settings.

-----------------------------------------------
FROM: Seth Leigh
DATE: 10/27/1998 13:40:30
SUBJECT: RE:  Intel PR440FX
-----------------------------------------------

. . .
---   2x      ---------> front of computer, away from cpus
. . .
  ---

. . .
---   2.5x
. . .
---

. . .
  --- 3x
. . .
  ---

. . .
  --- 3.5x
. . .
---

-----------------------------------------------

In addition, the jumper block J12B2-M, which is off towards the middle of the board from the J12B1 block, needs a bit of explaining.

There are two jumpers on J12B2-M.

• The first, which is manipulated by shorting either pins 1-2 or pins 2-3 (on the left side), controls the DIMM EDO memory access speed. 1-2 is 50ns, 2-3 is 60ns.
• The other jumper, which Intel says not to change, is actually a bus turbo jumper! If you set this jumper, it will increase the speed of the FSB by approximately 5%. So if you had a 66MHz FSB set otherwise, and you set this jumper, you will end up with about a 69.6MHz bus. Free speed!

This jumper was probably used by engineering to "over-test" the board and make sure that it not only met specs, but exceeded them as well.

This board also does not seem to pick up the emulated keyboard/mouse signals from some Aten and Hawking KVM switches. As a result, you have to be actually switched to the KVM port that the PR440FX is on, at least until the BIOS initializes the keyboard and mouse (lights on keyboard flash), or else you won't be able to use the mouse or keyboard once the machine boots.

The PR440FX does not have a boot order option for external boot devices. Therefore, if you have an IDE or secondary SCSI controller with its own BIOS, that BIOS will take precedence over the on-board SCSI for booting. The only way I found to boot off the SCSI disk instead is to make a boot CD and set the BIOS to boot off the CD. here is a script I wrote to automate this - you will probably have to customize it. The steps are - install grub onto a floppy, copy /boot/grub onto the floppy, make an image of the floppy, then make a bootable CD image with mkisofs that boots the GRUB floppy image. Once you have the ISO file just burn it to CD. It would be a good idea to have a /vmlinuz and /initrd links to your current kernel and use those as a GRUB menu option, so that you don't have to burn a new CD every time you install a new kernel.

Have fun! Mail me with any hardware-related questions regarding this board.