More than two M/board power sockets

h4rm0ny · 13 Jan 2019 at 09:39

Simple question, likely a daft question. I recently bought a motherboard that has the usual 20-pin ATX power socket along with the usual extra 8-pin CPU power socket. My PSU (a Corsair HX 750W) has hard-wired cables for both of these, it's connected up and running fine. However, unlike any previous motherboard I've owned this has a second 8-pin CPU power socket. I'd like to connect it up for the sake of overclocking but my PSU doesn't have the cable.

Is it normal these days to find PSUs with two power socket outlets? Can you convert to it from a PCI-E power cable?

agw_01 · 13 Jan 2019 at 10:13

My EVGA 850 G2 has 2 EPS connectors but an old Corsair TX850 I have doesn't, so maybe it's a recent thing on higher quality PSUs.

I have a dual socket Supermicro board which has 2 EPS connectors and it seems pretty happy with one of them running from a PCI-E cable with an adapter. If the PSU has a single 12v rail, there should be no difference where the power comes from.

h4rm0ny · 13 Jan 2019 at 11:21

agw_01 said:
My EVGA 850 G2 has 2 EPS connectors but an old Corsair TX850 I have doesn't, so maybe it's a recent thing on higher quality PSUs.

agw_01 said:
I have a dual socket Supermicro board which has 2 EPS connectors and it seems pretty happy with one of them running from a PCI-E cable with an adapter. If the PSU has a single 12v rail, there should be no difference where the power comes from.

Thanks.

I found this:
https://www.overclockers.co.uk/akasa-pci-e-to-atx12v-cable-adapter-ak-cb051-cb-033-ak.html

But it has six-pin output rather than 8. I am very cautious about doing things I don't understand with a £400 motherboard! What adapter are you using?

ANDARIAL · 13 Jan 2019 at 11:28

h4rm0ny said:
Thanks.

I found this:
https://www.overclockers.co.uk/akasa-pci-e-to-atx12v-cable-adapter-ak-cb051-cb-033-ak.html

But it has six-pin output rather than 8. I am very cautious about doing things I don't understand with a £400 motherboard! What adapter are you using?

I actually bought 2 of these recently
Was going to use on my X470 mobo,but in the end i didn`t bother as it is running fine (no OC as yet only set it all up xmas)
What i will say is the end has a 8 pin plug so if you need a 4 pin,as i do,the clip will not engage

agw_01 · 13 Jan 2019 at 11:35

What motherboard do you have? Don't think I've seen dual EPS connectors on a consumer/enthusiast board before.

I'm just using some cheap adapters from eBay but they seem decent quality with good gauge wires. Not overly critical about that machine though, it's only running a pair of 1366 Xeons and not overclocked.

You'll probably find that the wiring from a decent PSU is more than enough to comfortably handle the current drawn through a 6 to 8 pin adapter. Just make sure the connections are secure.

ANDARIAL · 13 Jan 2019 at 11:37

Me or OP?
I got the Gigabyte X470 Aorus Gaming 7 Wifi

agw_01 · 13 Jan 2019 at 11:39

Sorry, the OP

h4rm0ny · 13 Jan 2019 at 11:59

agw_01 said:
What motherboard do you have? Don't think I've seen dual EPS connectors on a consumer/enthusiast board before.

I'm just using some cheap adapters from eBay but they seem decent quality with good gauge wires. Not overly critical about that machine though, it's only running a pair of 1366 Xeons and not overclocked.

You'll probably find that the wiring from a decent PSU is more than enough to comfortably handle the current drawn through a 6 to 8 pin adapter. Just make sure the connections are secure.

MSI Meg Creation X399 for Threadripper.

(top-right connectors)

lee32uk · 13 Jan 2019 at 12:00

What TR cpu do you have ?

h4rm0ny · 13 Jan 2019 at 12:02

lee32uk said:
What TR cpu do you have ?

TR 1920X. But I plan to upgrade to a higher core 2nd Gen later on when the prices have fallen.

lee32uk · 13 Jan 2019 at 12:39

I am guessing your psu isn't the newer Platinum HX750 ? as that one definitely has 2 x 8 pin. Not sure about the older Gold rated units though.

I would probably play it safe and run at stock until you can get a definite answer. Maybe try asking 8Pack in his subforum or someone like that

h4rm0ny · 13 Jan 2019 at 12:41

lee32uk said:
I am guessing your psu isn't the newer Platinum HX750 ? as that one definitely has 2 x 8 pin. Not sure about the older Gold rated units though.

I would probably play it safe and run at stock until you can get a definite answer. Maybe try asking 8Pack in his subforum or someone like that

No, it's seven years old, iirc. It's been a real trooper. Buying a new PSU isn't out of the question as I'll be selling off the old PC and it will need a PSU to go with it (although it will be overkill). Still, it would be handy if a £4 cable can sort me out.

lee32uk · 13 Jan 2019 at 13:12

To be honest if it was Me I wouldn't risk overclocking with a 7 year old psu on a £500 board. I would keep it running at stock and then look to change out the psu for an RMx or similar, especially if going with a higher core count down the line. The pc would probably just shut down if the psu couldn't cope, but best to play it safe when running expensive kit.

agw_01 · 13 Jan 2019 at 13:18

Agree with Lee. For the sake of £100 or so, I wouldn't risk an old PSU when overclocking a machine like that.

h4rm0ny · 14 Jan 2019 at 09:16

Well I'm not planning to do any major over-clocking. Just a very minor bump. I would like to know what my options are for when I do put a newer chip in. I used an online PSU calculator to work out what the needs would be - all my drives, fans, GPU, etc. - and it actually only recommended 650W and said my 750W one was more than adequate. I'd sooner not buy a new supply if a £5 cable will do the job. I just need to know which cable, if possible.

Though I can buy a new PSU if need be. I have to order another drive from OCUK today, so if I'm going to get a new PSU it would be nice to roll it in with that.

h4rm0ny · 14 Jan 2019 at 13:25

https://www.corsair.com/us/en/Categ...h-all-CORSAIR-type-4-pin-out-PSU/p/CP-8920141

This looks like it would fit both the PCI-E sockets in my PSU and the 8-pin power socket on my motherboard. (I know that's another seller but they're American so irrelevant to here so hope that's not a breach of the rules).

The square and domed shapes of the individual pin sleeves match up. Is it safe to plug that in?

lee32uk · 14 Jan 2019 at 15:48

According to the tech specs that cable fits an RMx, RMi and SF series power supply. Plus your unit won't have a spare 'EPS' socket on the psu housing for it to plug into. If it did then you would already have the required cables. The RMx, RMi and SF units have 2 x 8 pin EPS as standard on the higher wattage units.

If you want to risk using an adapter cable then go with the Akasa one you linked earlier if you have a spare pcie connector to plug it into.

h4rm0ny · 14 Jan 2019 at 18:17

lee32uk said:
According to the tech specs that cable fits an RMx, RMi and SF series power supply. Plus your unit won't have a spare 'EPS' socket on the psu housing for it to plug into. If it did then you would already have the required cables. The RMx, RMi and SF units have 2 x 8 pin EPS as standard on the higher wattage units.

If you want to risk using an adapter cable then go with the Akasa one you linked earlier if you have a spare pcie connector to plug it into.

My PSU has spare sockets that are 8-pin and used for PCI-E. The shape of the pins looks to be the same as the PSU. I don't want to risk anything. I just want to know if they're meant to be / okay to be connected to an ATX 4+4 power socket. The cables I've found look like they'd fit, but I can't find any clear information anywhere on whether you're supposed to do this or not.

lee32uk · 14 Jan 2019 at 18:37

h4rm0ny said:
My PSU has spare sockets that are 8-pin and used for PCI-E. The shape of the pins looks to be the same as the PSU. I don't want to risk anything. I just want to know if they're meant to be / okay to be connected to an ATX 4+4 power socket. The cables I've found look like they'd fit, but I can't find any clear information anywhere on whether you're supposed to do this or not.

A pcie connector is different to an eps connector though in the way they are wired. Also the connector itself is slightly different.

h4rm0ny · 14 Jan 2019 at 19:15

lee32uk said:
A pcie connector is different to an eps connector though in the way they are wired. Also the connector itself is slightly different.

Thanks. That's very helpful. So it looks like this will do the job.

https://www.overclockers.co.uk/akasa-pci-e-to-atx12v-cable-adapter-ak-cb051-cb-033-ak.html

£2.39 seems a lot cheaper than a whole new PSU!