Question about SATA power connectors

Hi everyone, i see many R2 pictures with twa onboard SATA power connectors : one with 2 pin and one with 4 pin… but as you can see on the picture my R2 got 2 connectors with 2 pin!


is it normal ? how can i do for an 3.5" HDD ? i have to replace the connector ?

thank you for your replies.

Hi Karon,

Arm boards, not only this one but mainly all of them, are not designed for native use with 3.5 HDD’s. They fit only for 2.5 laptop HDD’s. There is a reason for it : 3.5 HDD’s need double power feeding : 12V and 5V. So, your snap describes well a 2.5 HDD power connector on the board. It fits for cables made for this purpose :,searchweb201602_4_10152_10065_10151_10344_10068_5722815_10342_10343_10340_10341_5722915_10698_10697_5722615_10696_10084_10083_10618_10305_10304_10307_10306_10302_5722715_5711215_10059_5723015_10184_10534_308_100031_10103_441_10624_10623_10622_5711315_5722515_10621_10620,searchweb201603_28,ppcSwitch_3&algo_expid=4ba737bc-e083-4f55-aa1d-b09c106fb6a8-15&algo_pvid=4ba737bc-e083-4f55-aa1d-b09c106fb6a8&priceBeautifyAB=0 . Therefore, a 3.5 HDD can be plugged with an USB kit like this one:,searchweb201602_4_10152_10065_10151_10344_10068_5722815_10342_10343_10340_10341_5722915_10698_10697_5722615_10696_10084_10083_10618_10305_10304_10307_10306_10302_5722715_5711215_10059_5723015_10184_10534_308_100031_10103_441_10624_10623_10622_5711315_5722515_10621_10620-5711315,searchweb201603_28,ppcSwitch_3&algo_expid=9c801748-201d-4722-a05e-cbe95bfc8399-2&algo_pvid=9c801748-201d-4722-a05e-cbe95bfc8399&priceBeautifyAB=0 . If you have a sufficient knowledge in electronics and are able to built things in some homemade case with internal SMPS , then you can built it around some power splitter cables like this :,searchweb201602_4_5722916_10152_10065_10151_10344_10068_5722816_10342_10343_10340_10341_10698_10697_10696_5722616_10084_10083_10618_10305_10304_10307_10306_10302_5722716_5711216_5723016_10059_10184_10534_308_100031_10103_441_10624_5722516_10623_10622_10621_10620_5711316,searchweb201603_28,ppcSwitch_3&algo_expid=4680e681-3186-4596-8603-a0796f2cef24-0&algo_pvid=4680e681-3186-4596-8603-a0796f2cef24&priceBeautifyAB=0.

In such a case, you should manage the power-off procedure for your HDD through a supplementary button, co’s the board will not automatically shut your disk down when powering off !

Regards, Paul.

That’s right. The power connectors on the BPI R2 are only for 2.5" HDDs. My solution for this is an old PC power supply with bridged power-on pin

Here you can find some other idea on how to power 3.5" HDD with R2: BPI-R2 boot / power suppy.

There is 12 volt 2 pin on the picture.12 volt pin is empty.Can I to replace the connector?Do I use 3.5" sata HDD? I have 12 V 2 A power adapter for BPI-R2.Screenshot_20180419-104205

I know it’s quite an old post but maybe there is some update in that subject. As @Rahmi_Ozdemir pointed above, layout marks printed onto PCB, leads to conclusion that it could be possible to desolder old socket and mount one, that iclude another GND and 12V line. This could introduce compatibility to 3.5 inch drives. I’ve stumbled upon some photos of R2 (old revolutionary board?) that actualy had that bigger socket. Was it working back than for 3.5 drives?

I don’t think connector can bring enough current for spinning up 3.5 inch hdd (imho needs 2A alone)

I’ve looked into my HDD spec sheet (WD10EFRX) and as I saw, it consumes 1,2A at peak. Couldn’t find precise data about R2’s average power consumtion but basead on informations about recommended power supply (12V, 2A), I assume that something with 3,5-4A should be fine. May be it would do the trick? Unfortuantly, for now I’m using 3A power supply for R2, so it might not be enought :confused:

I guess r2 cannot bring more current to sata powersocket.

You can try it but i guess you will experience instability when powering 3.5 inch hdd over r2.

R2 alone (without pcie card,hdd,…) is ~5-6w (=12v ~500mA) based on load,so even 2A should be enough

The 12V pin is directly connected to DC input.

I’ve replaced the default 2-pin socket with 4-pin, and use it with 2.5" WD VelociRaptor WD1000CHTZ-0. (12V current is rated to 0.35A, IDK about spin-up peak current). My R2 works stable with a 2A power supply, including spin-up on power-on. Also, HDD remains powered-off with DC plugged-in, and R2 is powered off.

So your case is pretty much simmilar to mine. As You pointed out, after connecting power supply, the 12V line is immediatly feeding that 12V to the pins in socket but 5V line is not. I checked it with voltmeter and it starts delivering 5V to the pins after the boot process (after few seconds of pressing power button). I’m curious how it affects a drive, when it has 12V from the begining and gets 5V after some time. Have you done someting like bridging power button or does it work just like that, with few seconds of delay?

As I know 12V is only for mechanics when 5v is for MCU/logic (correct me if I wrong). So in case when mechanics is controlled by logic it should be ok for a HDD, when it has permanent 12V, anyway it starts/spins up only when it has 5V, which is controlled by SoC’s power button.

P.S. It’s only my opinion that might be wrong, so all modifications are at your own risk :wink:

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