4Pin 12V Power - Supermicro Motherboard Question

[T_Minus]

Getting ready to rack some new gear and of course it would appear I'm missing an adapter or this isn't needed...

Motherboard: Supermicro | Products | Motherboards | Xeon® Boards | X10DRX

Chassis: Supermicro | Products | Chassis | 3U | SC835XTQ-R982B

The motherboard manual states all power adapters are needed, but then it states the 2, 8 PIN 12V are (REQUIRED) and that same (REQUIRED) text is not under the 4 PIN 12V.

The chassis (which I got from a member here, maybe he has some ideas) doesn't have a 4 PIN 12V power plug, which I thought was weird considering the chassis is one suggested (one of the few that fit this board) on SuperMicro's website...

 

[britinpdx]

I doubt you'll need the 4pin plug.

I have an X9DRD-iF that also has 2x 4pin sockets in addition to the 2x 8pin EPS12V sockets.

However, the manual states "Be sure to connect the 24-pin and the 8-pin power connectors to your power supply for adequate power delivery to your system. The 4-pin power connectors are optional; however, Supermicro recommends that these connectors also be plugged in for optimal power delivery."

Optional was good enough for me and I didn't bother trying to rig anything up. The SM chassis that I was using had no spare 4pin 12V anyway. Works fine with a couple of E5-2670's.

I'd be interested to find out why the 4pin 12v supplies are needed ...

 

[herby]

I've only owned/played with 2 models of Supermicro boards and one was pickier than the other about 12v connectors.

My H8SCM-F boards are single socket and were happy with either a 4-pin 12v connector or the manual mandated 8-pin connector.

My H8DCL-6F board is dual socket and will not boot without two 8-pin 12v connectors connected. Even with just one socket populated if you try 8-pin + 4-pin the board refuses to boot and angrily beeps at you for the audacity of disobeying the manual.

Luckily for the H8DCL-6F I had a 4-pin 12v/molex to 8-pin adapter that seems to satisfy it:

StarTech 6in 4 Pin to 8 Pin EPS Power Adapter with LP4 - F/M (EPS48ADAP)
Amazon.com link

________
Xenservers
-big-red: Supermicro H8DCL-6F, 4332 HE x2, 32GB ECC, USB boot, 6950
-lil-red: Supermicro H8SCM-F, 4376 HE, 16GB ECC, USB boot, 6450

Freenas
-blue: Supermicro H8SCM-F, 4376 HE, 16GB ECC, USB boot, 240GB M500 x3, H310
-SE-3016: 1TB WD10EACS x2, 2TB 5k3000 x2, 3TB DT01ACA300 x2

 

[T_Minus]

Depending how my testing goes I could be using 6-8 PCIE slots for NVME drives & NICs, now that's not capacity for my board so I'm hoping I don't need it, but I want to be sure my system is "stable".

I have a couple Molex --> 4pin/12v adapters coming from amazon just to be safe

FWIW - It booted fine w/out it. Then again there's nothing plugged in to it either, just 1 stick of ram, 2 cpu, and mboo