The AUX-connector is mainly for extra 3.3V current, with just a single 5V wire, so only increases capacity there by 25%. It's mainly for AGP and PCI power, as the manual says:

The Secondary Power Connector is recommended when a heavy load of peripherals has been connected to the motherboard. […]
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The Secondary Power Connector
is recommended when a heavy
load of peripherals has been
connected to the motherboard.

In fact the picture of the P6DBE in the manual shows the AUX power connector not even implemented on the board (with some kind of sticker in the place it would go)...

I wouldn't worry about the AUX connector unless you have utterly stuffed that system with power-hungry cards. Note that it's still fairly doable to find PSUs that have it, in particular a lot of the 5V-heavy Fortron (FSP) power supplies used by many OEMs in the late 1990s/early 2000s have it, in fact there are even some that have both ATX12V CPU and AUX connectors. They were frequrently relabeled AOpen and Sparkle in this part of Europe. In general they were very solid designs, but by now a re-cap may be a good idea.

batmreload wrote on 2025-08-17, 10:19:

Has anyone run anything faster on this board? I know its limited to a 100mhz bus, but I seem to remember faster P3's, maybe up till 1ghz, in the 100mhz bus speed.

I have 2 x Intel Pentium IIIE (Coppermine) 1.00GHz [cC0] @ SL4KL in my Gigabyte GA-6BXD, in general if a board will run 850 MHz it should run 1GHz.

I currently only have 2 800mzh slot 1 running on my P6DBE but on my P6DGS I have had 2 1.1ghz on slotkets running win2k. On both machines I have not been running the 6 pin connectors although I do have some power supplies with them.

On my P6DGS not knowing a ton on electronics I'm more concerned of the voltage regulators for cpus of that speed on that board, they do get a might toasty. SM only mentions cpus of 800-850mzh on those line of boards and the the power usage of the cpus do go a bit higher above those.

You do not need to put anything on the AUX power connector. Now if you're planning on filling the motherboard with PCI cards that pull the maximum allowed current, this becomes a different story.

I think some later BIOS versions will allow for 133mhz operation, but dont quote me on it.

Haven't run this particular board from SMs dual P6 series, but have run the P6DBU & P6DGU without ever needing to connect the AUX power cable.

Generally, the later revision boards (2.xx or greater) with the uprated VRM chips were at least GHz capable - https://web.archive.org/web/20040216174937/ht … s/Processor.htm

If the board has an AMI WinBIOS, there may be an undocumented setting under 'Chipset Setup' titled Manufacturers Setting (default / recommended Mode 0) which allows for setting the following bus speeds...

Mode 0 - 100Mhz
Mode 1 - 100Mhz
Mode 2 - 106Mhz
Mode 3 - 112Mhz
Mode 4 - 83 Mhz
Mode 5 - 133Mhz

Also, just FYI: https://www.minuszerodegrees.net/manuals.htm#Supermicro

Archived what I had a few years back. factory driver CDs/manuals/PDFs etc. Cheers.

PC Hoarder Patrol wrote on 2025-08-18, 13:11:

Generally, the later revision boards (2.xx or greater) with the uprated VRM chips were at least GHz capable - https://web.archive.org/web/20040216174937/ht … s/Processor.htm

I have that link bookmarked from years ago and thats why I worry about my P6DGS running the 1.1ghz it has the Cherry CS5155 on a 2.1 rev board (as seen here https://theretroweb.com/motherboards/s/supermicro-p6dgs) and according to that page it says 850mhz on rev 2.x and although the P6DGS isnt mentioned by name there is also

*440BX/440GX models not listed above are not recommended to use any CPU above than 600MHz.

I would guess at least 850mhz would be fine.

I have looked up the Cherry CS5155 datasheet but with my limited understanding I'm still unclear if its fine, I dont have a good understanding of power circuits. I know its fine voltage wise Im just concerned of pulling too many amps through it.

It is SM and they tend to over build most things is my impression.

My Tyan tiger 100 is stable with dual coppermine at 850 but not higher fwiw