pcie for 8pin cpu power?

[matexoza]

anyone know if i can use this to power an 8 pin xeon cpu?

[FloRolf]

no, they won't fit.

[asdf2061]

No. Don't do it. The voltage and stuff is different. Use the 8-pin CPU power instead.

[matexoza]

ya i am i only have one tho lol the board has 2

any ideals on a mod to make a 8x

 

[Godlygamer23]

2 minutes ago, I_IHaveNoLife_l said:

No. Don't do it. The voltage and stuff is different. Use the 8-pin CPU power instead.

The voltages are the same(12V). The pin-outs are different though.

[daniellearmouth]

Just now, matexoza said:

ya i am i only have one tho lol the board has 2

any ideals on a mod to make a 8x

 

If the board has two and you only have one, it doesn't matter. Just plug it into one of them.

[Electronics Wizardy]

1 minute ago, matexoza said:

ya i am i only have one tho lol the board has 2

any ideals on a mod to make a 8x

 

Get a splitter.

[matexoza]

for the 8 pin cpu?

 

[WereCat]

You can't plug PCIe 8pin into 12V ATX 8pin.

However if your PSU has only 4pin ATX connector use that one, it will work without the other 4pins as long as you are not using very power hungry CPU.

[matexoza]

it is currently only pluged into one but i want to run both cpus

 

i forget what cpu tbh i been playen with this for a while lol its a build with old server parts like the one linus built there 56xx something or other cpus seams to be running ok on the one cpu trying to load windows on it atm haven problems finding the hdd atm

[mariushm]

You can buy 8 pin eps / power extension cables and just cut the wires and attach them to the wires from the pci-e cables with a  bit of solder.   The black wires are ground, the yellow ones are 12v ... connect ground wires to ground wires, 12v wires to 12v wires

No clue about the country you're from , so I can only suggest a somewhat universal store: https://www.amazon.com/StarTech-com-8-Inch-8-Pin-Extension-EPS8EXT/dp/B000M802RG/ref=sr_1_1?s=electronics&ie=UTF8&qid=1475880206&sr=1-1&keywords=eps+power+extension++cable

 

If you don't want to cut cables from your current power supply you may be able to find adapters that convert 2-3 molex (hdd)connectors to one of those 8 pin EPS connectors though such adapter cables usually aren't that great quality to begin with and should only be used with processors with TDP of let's say 65-95w, nothing higher. Here's an example of such a cable : https://www.amazon.com/Funnytoday365-Motherboard-Supply-Adapter-Converter/dp/B01LJQWJPW/ref=sr_1_8?s=electronics&ie=UTF8&qid=1475880373&sr=1-8&keywords=molex+to+eps+adapter+converter++cable

 

[matexoza]

ill find one of each at work and try both i work at an escrap recycling place only server hardware is pretty ez to comeby if i cant find them ill just buy them there pretty cheap fyi that was your 666 post lol 

[Drak3]

The PCIe and CPU power cables have different pinouts. A pair of wires are switched between the two cables, and using PCIe for your CPU or vice versa will most likely fry your component.

You can probably find a plethora of splitters and adapters out there, but you're probably better off finding a power supply made for dual socket boards.

[manikyath]

22 minutes ago, I_IHaveNoLife_l said:

No. Don't do it. The voltage and stuff is different. Use the 8-pin CPU power instead.

the voltage is the same, the pinout is different

 

if you're clever and daring you could try to bodge it, but for the love of god please dont.

[matexoza]

20 minutes ago, Drak3 said:

The PCIe and CPU power cables have different pinouts. A pair of wires are switched between the two cables, and using PCIe for your CPU or vice versa will most likely fry your component.

You can probably find a plethora of splitters and adapters out there, but you're probably better off finding a power supply made for dual socket boards.

 

just used one i had laying around im only about 50 bucks into this atm was on the case its a pink one for my little girl ;p

 

i already ordered that Molex splitter 

[mariushm]

The pci-e connectors have three pairs of 12v + ground wires. the 8pin pci-e connector has two additional ground wires.

So, if you were to blindly create a connection between pci-e connectors and eps connector you'd have to issues.

1. on one of the connectors the 12v wires are on the top row, on the other connector the 12 wires are on the bottom.

2. on the 8 pin  pci-e connector, the fourth wire in  the row with 12v wires is ground, so if you were to blindly connect the row to the 12v row in the eps connector, you'd create a short between 12v and ground, effectively turning that wire in a fuse.

If you're lucky, the power supply would have an over current protection and stop working until you disconnect the short. if you're not lucky, the power supply would dump 2-300 watts through that cable melting its insulation and then basically heating the copper in the cable to the point where it starts melting in a pool of copper at the bottom of the case.

 

Anyway, as long as you're aware of that and you connect 12v wires to 12v wires and ground wires to ground wires, you would be fine.

Also, in theory, each cable if it's AWG18 is capable of carrying 8-10 A of of power (about 120w) so even just two wires would be capable of giving a cpu enough "juice" to work. Thre three pairs of 12v+ground in a 6pin or 8pin pci-e connector would be more than enough to give power to a cpu, so you can connect the fourth pair of wires in the eps connector to one of the three pairs of wires in the pci-e connector without worries.

With the molex to eps adapters, the reason why it's not recommended to use powerful processors is because most of the time these adapters are using AWG20 or thinner wires (which can only handle about 6A continuously) and in addition the contacts in the molex connectors are not really designed for high currents, they can only do about 5-6A of current.  So two molex connectors would only give you in complete safety about 10-12 A of current at 12v, or about 150 watts - enough to give peak currents for up to 95w tdp cpus but not really recommended for more powerful cpus or if you plan to do overclocking.

 

// and now i have 667 posts

[matexoza]

ty for all the info i just assumed at the start wrong connector tips wrong power just wanted to confirm anyway the cpus had passive coolers on them and they already started to overheat sooo i have to get some fans tomorrow lol and figure out why the sata ports won't find my hdd but im pretty sure that's just some bios settings 

[Naeaes]

5 minutes ago, matexoza said:

i already ordered that Molex splitter 

Good luck! I suspect you'll burn your PSU.

 

If your PSU could power the CPU, it would do it over the single 4-pin EPS. It's rated for 75 Watts at 12VDC (+/-10%). Splitting the 4-pin into an 8-pin will trick your motherboard into believing that you have a 150W connector plugged in. But in reality the wires come together and it's just the 75W. Run twice the rated power through a cable and you probably guess what'll happen? 

 

Now you may have a tiny chance of success if a) your PSU can provide well over 75W to the CPU but they just chose to put the 75W connector in it for some reason. Or b) the CPU actually can run at less than 75W but the motherboard is for some reason designed to require the entire 8-pin. 

 

All again stress that if your PSU can provide enough power to your CPU, it can do it over the 4-pin without a splitter of any sort. If it needs a splitter, it's not rated to provide such high current and it'll burn either right off the bat or at some point over time. Just plug the 4-pin into the 8-pin like so (to the right with the clip up). If it works, you're golden, if not, go PSU shopping.

 

The very least you should definitely back up your data before trying. 

[matexoza]

i literally pulled every part out a scrap bin there is no data yet

 

[matexoza]

now here's a question if i only have 1 cpu power plugged in why are both cpus hot?

[matexoza]

bios registers both cpus with only 1 power cable ;p might not need anything lol

[mariushm]

the two EPS connectors may be connected together to one big copper plane on the motherboard from where both VRMs take the power they need. In effect, if this is what happens, you feed both CPUs from a single EPS connector. It would be strange because on most server motherboards they would implement some current sense to detect if both EPS connectors are plugged and refuse to start (or trigger at the very least some warnings) if that's not the case.

you still have an issue of how much current can be safely transferred from the power supply to the cpu vrms.. keep in mind each wire can safely transport around 8-10A, so if the cpus together use more than it's delivered through the four 12v pairs, you could overheat the wires or burn the connector.

Your system may also work now at boot when the cores are idle and your cpu uses little power but may crash or be unstable in benchmarks or various cpu tests.

 

[matexoza]

ima try to bench when its all done loading windows i putt a box fan on the case and dropped the room temp to about 60-65 sooo   im cold lol but its not over heating atm 

 

im pretty shore the cpu is 2x 

http://ark.intel.com/products/47923/Intel-Xeon-Processor-E5640-12M-Cache-2_66-GHz-5_86-GTs-Intel-QPI

 

[matexoza]

windows loaded so far so good

[matexoza]

285 on cinebecnh if anyones intrested it only ran 1/2 cpus