March 13, 2001 -- The Intel Providence mainboard (PR440FX) is, in my opinion, one of the best dual Pentium Pro mainboards available. It has IDE channels, onboard 100BaseTX ethernet (via an Intel EtherExpress Pro/100), onboard sound (a Crystal CS4232), and onboard Ultra Wide SCSI (an Adaptec AIC-7880 chipset, the same chipset in an SGI O2). It has virtually everything you need, except a video card.
I got my board from a second-hand dealer called The Computer Geeks Discount Outlet. The board only cost me $89 when I bought it in the summer of 1998. I couldn't believe I'd found a board with all of that for so little. I bought two 180MHz Pentium Pro processors to go in it (those were $120 each in the summer of 1998). The resulting machine became my workstation until the beginning of 2001, when I moved over to using my Sun Ultra 5 as a primary system.
Through the years of using the PR440FX system, I had upgraded to Ultra160 SCSI, upgraded to dual 200MHz PPros with 1MB L2 cache each, upgraded to 256MB of RAM (started with 128), and added tons of hard disks and CD drives and so forth. The system worked very well and never presented any problems. That's not to say I didn't have complaints.
Most of the complaints I had were silly. Like you can't disable the onboard SCSI controller. But the big one was the CPU clock settings. The board only documented the settings for a 180MHz processor and a 200MHz processor. Intel also made 150 and 166 MHz models of the Pentium Pro, but nothing faster than 200.
Looking at the board, you could tell that it was capable of so much more. I mean for two processor settings, there sure are a lot of jumpers. What do they do? Can I overclock the system? A lot of people know that the Pentium Pro was one of the easiest processors to overclock since everything in the chip ran at the same clock rate. There were no side effects when I clocked my 180s at 200. Granted, that's not a big jump, but it's still a jump.
I asked around to see if anyone knew of undocumented jumper settings for the PR440FX. Searched the web, searched USENET, searched all over. I was posting some questions to Intel public discussion forum for their Pentium Pro mainboards and decided to ask about overclocking/undocumented jumper settings. Well, this post was promptly deleted by an Intel Troll, but about ten minutes later I got an email from someone who had seen the post during the short duration it was online and had emailed the jumper settings to me. The board supports all of the Pentium Pro CPUs (150 - 200) and can even be clocked up to 266MHz!
In an effort to help document the undocumented jumper settings for this mainboard ("give back to the community"), I'm posting them here. Remember that overclocking in dangerous and voids your warranty. Use with caution and don't be stupid. Do not come to me if you fry your system, in other words.
| 150 MHz (60 MHz bus x 2.5) | ||||
| 166 MHz (66 MHz bus x 2.5) | ||||
| 180 MHz (60 MHz bus x 3.0) | ||||
| 200 MHz (66 MHz bus x 3.0) | ||||
| 210 MHz (60 MHz bus x 3.5) | ||||
| 233 MHz (66 MHz bus x 3.5) | ||||
| 266 MHz (66 MHz bus x 4.0) | ||||
|
J12B1: F up = 60MHz F down = 66MHz
J12B2: |
Multiplier: E up G down H up = 4X E down G up H down = 3.5X E down G down H down = 3X E down G up H up = 2.5X any other E G H = 2X |
UPDATE: 03-Dec-2001 -- big_al provided me with these jumper settings for the VS440FX mainboard. Hopefully users of those boards will find the following chart handy. Thanks big_al!
|
Bus: 60MHz = jumper 17-19 66MHz = jumper 19-21 |
Multiplier: 2X = jumper 10-12,9-11 2.5X= jumper 10-12,11-13 3X= jumper 12-14,9-11 3.5X= jumper 12-14,11-13 |
Well, there they are. I'm hoping this page will be picked up by the search engines so that when someone tries to search for "jumper settings pr440fx" like I did, they'll get some useful information. I hope Intel finds this too so they can see what information they left out of that puny little manual that came with the board.