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4 pin to 8 pin EPS12V adaptor

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ok, so i built my new box yesterday and i realized my power supply does not have the 8 pin eps12v connector on it

http://www.xoxide.com/hiper-power-supply-blue.html
(i really like the power supply and would like to continue to use it if possible)

they sell a 4 pin p4 to 8 pin EPS12V adapter here:
http://www.xoxide.com/tt-psu-adaptor-cables.html

has anyone used one of these adapters? i can't find any info on them.

for the record my system is an amd64 dual core X2 3800+
MSI k8n Diamond plus mobo
2Gb corsair XMS
and a Geforce 7900 GT KO

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The adapter should work out fine for your setup 8)

if you were trying to run a dual-xeon server I would worry a bit since the amps on that aux connector can add up really quick!

Reply to doolittle

muchas gracias amigo!!!!
that just made my day

i stopped by a local store that sells computer stuff and the guy said i can probably just plug in the 4 pin p4 connector without using a adaptor and it should work. he made it sound like he has done it before. anyways i've got the adaptor on order and it should be here by the weekend.

thanks for the answer though, i'll post back with my results

can't wait to use my new system!!!

Reply to QuickDraw

theres a downfall to those adapters
If a company says a tru 8pin molex and a tru 24pin power connector, they mean it. My friend had the same problem and wound up having to replace his mobo.
Not a great idea but if one cannot afford a psu, one must burden for an adapter.
-Good Luck-
:twisted:

Reply to bluntside

Quote :

Most boards will run with a 4 pin in the 8 pin spot.
The deal is you now have HALF the wire to carry current.

I would use the 4 pin and grab a Molex-4 pin adapter....this will give you the extra current supply.

The adapter is $3 in shops or 99 cents online at SVC.

Z

Reply to ZOldDude

great suggestion, i'll try to power it up using the 4 pin connector tonight, if it doesn't work i'll run to the computer store to see if they have the molex to 4 pin connector that seems like a good soultion.

the molex connector has 1 wire that's running at 12V while the p4 connector has 2 and 2 ground wires(with the molex i would gain 1 wire running at 12v), the molex adapter to p4 would get me as close as i'm going to get with my current psu.

Reply to QuickDraw

ok it worked with no adapter just the p4 connector is connected, OH MY!!!!!
what a computer!!!!! major step up for me.
thanks for all the help!

Reply to QuickDraw

It worked, like mine did (mobo ASUS P5Q3 with 8 pin aux power connector jack) with only a 4 pin connector inserted.

Problems arise when u try to add stuff to youre mobo:
I plugged in a PCI NIC and the system didn't boot the first time.
I plugged the NIC in the second PCI slot and it worked fine, until I plugged the LAN cable in it, then my Windows froze and I had to restart and tear the NIC out

The logical conclusion is that i powerd only part of the mobo's circuitry with that half connector (4 pin instead of 8), or , at least, you can say it didn't have enough power to sustain a PCI device.

PS: I looked in my users manual for the p5q3 and it stated to only plug in an 8 pin connector for a "fully configured system".

Now i too am in a search for an adaptor

Reply to Anonymous

I am somewhat familiar with the ASUS motherboards. Some of the boards come with an 8 pin header on the motherboard. Four of the sockets are covered with a black plastic cap. On those motherboards you can use either a 4 pin or 8 pin power cable. Remove the plastic cover to use an 8 pin power cable. It's just not documented very well in the user's manual. I had to go to the ASUS forum to find the answer. However, there are high end motherboards that do require an 8 pin connection. In that case purchase an adapter. In fact I highly recommend it.

Message edited by JohnnyLucky on 03-07-2009 at 07:10:33 PM

Reply to JohnnyLucky

Friends --

This is all about supporting devices on modern motherboards that draw greater current than previous common devices. In order to move power from the connectors on the board to the devices (CPU, graphics card, etc.), the board manufacturers have "doubled up" on the foils carrying power within the board to such devices. For example, for newer multi-core CPUs, 8 lines instead of 4.

So while you can operate safely at moderate demand with 4 lines connected, the board (and perhaps the device itself) will be safer drawing through all 8 lines available on the board. Each carries lower current and is much less likely to build excessive heat through resistance. (Sorry if I'm being "techy." )

If an adapter is available (such as the one noted above), and you have such a situation, better to be safe than sorry. I'm in the process of building a new system and am ordering the cable. Meanwhile, I'll be sure not to tax the CPU to its max performance until the 4-8 pin conversion is accomplished.

Reply to Jazzman7

Here's a quick check. Remove all power. Ohms check the 4 +12 Sockets on the MB to each other ( not to gnd). if all 4 Plus pins read a short to one another then the 8 pin plug is only need if CPU power is above 135 W I believe (Refer my MB Book for P965-DQ6).
At power levels above the 120/135 Watts the purpose of the 8 pins vs 4 Pin is to reduce the IR drop of the individual socket/pin to prevent possible overheating (Sorry ZOldDude - it's not the wires as they 4 wires provide plenty of current capibility).

To OP, I dought you need the adaptor unless you OC and/or are close to 120/135 Watt CPU

If you find that 2 +12V pins are shorted, but isolated from the other two - then that is a different story. IE a MB designed to support dual proc and uses seperate VRs.

Added
There is an Advantage in using an 8 Pin connector with 8 wires even when not needed. You reduce the overall IR loss which increases the "Real" voltage delievered to the onboard VR, alas only maybe 0.05V

Message edited by RetiredChief on 03-16-2009 at 10:19:41 PM

Reply to RetiredChief

HI I have a 6 Pin PCIe and only a 4 pin 12V for the board - did any one try to slice the 6 pin into pair of 4 and 2 and to connect the 4 pair together?
As I see it it's the same voltage drown form a different rail of 12 V
The sys isn't stable with 4 pin 12 V alone.
Thanks, David

Message quoted 1 times

Reply to david_29

Hi
I am in the same situation as the OP. I have a Hiper HPU-4B580 PSU and I just updated my sytem to a Gigabyte GA-MA790FXT-UD5P running a AMD Phenom II X4 955. I attached 12v atx cable into the mobo's 8 pin socket and all seems fine. I have a Sapphire ATI HD4670 graphics card which has a passive cooler to keep the power consumption down.

This discussion suggests two alternative solutions to the 4pin/8pin interface.
Either attach an additionl cable from the PSU comprising a molex to a 4pin and plug it in next to the first 4pin plug or get an adapter to convert the 4pin into an 8pin

http://www.cclonline.com/product-i [...] t_id=30337

Will either conversion method deliver more power to the CPU when compared to just having the 4pin connected to the mobo.

Finally Hiper offer a solution which involves using their extender

http://www.hipergroup.com/products [...] action=FAQ (see question 3)

However this solution looks like it will use 3 of the PSU's modular connections which would limit my otions to connect other components to the psu unless it would be possible to connec the two molex connectors to one molex output.

Any thoughts

Reply to howardg

I am planning on buying a motherboard which has an 8-pin CPU power input, but also has a 4pin Molex input for "additional power". ZOldDude mentioned using simply the 4-pin CPU and the 4-pin Molex. Would that be equally safe as using the 8-pin CPU power connector for high intensity use?

This would be the motherboard
http://www.newegg.com/Product/Prod [...] 6813153151

Message edited by xiahoudun32 on 08-10-2009 at 03:14:57 AM

------------------------------ OH GOD HOW DID THIS GET HERE? I AM NOT GOOD WITH COMPUTER
Reply to xiahoudun32

david_29 wrote :

No, No, NO.

The pinouts are completely different. What you will do is ground out the 12 volt line. If you are lucky, the PSU will electronically shutdown, preventing any damage to the system. If you are unlucky, you will fry something.

Unless you have an EE CPU pulling more than 120 watts, your stability problems are not related to the 4 pin connector. You may have a flaky power supply, but that's not the same thing.

Reply to jsc

I just got this reply from Gigabyte technical support:

Answer : Dear customer,
Basically, if current power supply is 500W, you don't need to be using a 4 pin to 8 pin adaptor, jus plug the 4 pin connector close to the cpu side and the 8 pin connector system will work and run fine.

Reply to archp2008

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