I bought strike-x 1100W PSU to use it with a quad socket opteron server. The problem is the server needs three 8 pin EPS connectors while the PSU comes with 2.

Since its modular can i add another EPS cable i have laying around? And where should i add it? The pcie slot on the PSU has the right number of pins so can i add it there? If not is there anything i can do besides getting a new PSU?

Here is a picture of the power supply

enter image description here

  • Most modular power supplies connectors are not universal. – Ramhound Jan 30 '16 at 0:39
  • How do you mean? They are all the same? 8 pin EPS is 8 pin EPS? And if this one is could i add it? – User173 Jan 30 '16 at 0:44
  • I see 4 SATA connectors and 2 PCI-E connectors. I don't see a EPS connector. You cannot use the PCI-E or SATA connectors and plug them into the EPS connector on your motherboard. So you must be talking about cables coming out of the PSU itself. I was talking about the modular 6 cables your PSU has, they are normally not universal, and keyed to only allow stock cables or aftermarket cables ( i.e. designed to fit ). – Ramhound Jan 30 '16 at 0:47

Assuming it has the same pinout as your PSU - EPS is a bunch of 12V and ground anyway. The 'right' way to jerryrig this would be to use the Molex cables that should come with your PSU (aka, the oldschool molex/hard drive power supply), and connect that to a suitable 4 pin molex to 6 or 8 pin EPS connector as needed. This is the (relatively) safe way to do it.

You do not to wantonly plug it into a PCIe connector - the pinout/voltages may be different and a PCIe power connector is differently keyed anyway.

  • You mean use a molex to 8 pin EPS adapter? Is that safe? I mean, can so much power (4×140W total - so about 180W for that cable) go trough a molex connector? – User173 Jan 30 '16 at 0:50
  • The PSU has no molex cables - islabit.com/wp-content/imagenes/raul/22-fa-atx/… – User173 Jan 30 '16 at 0:53
  • I don't know where you get "4x140 watts, so about 180W total". The total power permissable through the EPS12V connector is 336 watts. So you're even more correct than you thought! One should absolutely not try to adapt the 4-pin molex drive connectors to EPS12V. You could be pulling up to 28 amps at 12 volts and the max for one Molex circuit is just 13 amps. There are adapters that let you power an EPS12V from two Molex connectors but even that would be iffy. – Jamie Hanrahan Jan 30 '16 at 6:14
  • Pretty sure the 7th cable from the top looks like a molex to me. Granted, the only reason to have a molex cable/connector is to convert to something else. – Journeyman Geek Jan 30 '16 at 6:18

PCI-E power and EPS12V connectors appear similar, but there are important differences:

  • EPS12V has four ground pins on 1-4, and four +12V pins on 5-8, possibly from two different rails.
  • The PCI-E power connector has +12V on 1, 2, and 3, ground on 5, 7, and 8, and sense lines on 4 and 6... almost the opposite.

Take a look at the two connectors here. See how the EPS12V has yellow wires (+12V) coming into the "top" of the connector (the side with the clip), while the PCI-E cable has black (ground) on the top? Right.

Since these are not the only connections to the PSU's +12 and ground in a typical computer, plugging a PCI-E power cable into an EPS12V receptacle, or vice versa, would almost certainly put a dead short across the power supply's output.

To keep you from making this mistake there are subtle keying differences in the connectors (in the shapes of the plastic insulation around each pin).

Therefore, even if you have a spare PCI-E cable for your modular supply, you will not be physically able to plug it into your motherboard's EPS12V connector. Nor would you want to.

An adapter would be possible. I found one: 1st PC Corp CB-6M-44F 12" 6-pin PCI-Express male to 4+4-pin EPS female From the picture you linked of your PSU the PCI-E output connectors are of the 6+2 type. So you could get that adapter and just plug the 6-pin PCI-E connector into it, then plug the EPS12V end of the adapter into your motherboard.

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