Installing a new PSU help

demongorgan · 04 Jul 2013

hi there, was just looking for some advise please.

I recently purchased a new 7850 GPU which requires a 6pin pci-e connector that my currant power supply does not have, also it was on the min requirement of 500w and being a cheap model figured it wouldn't output what I would need.

so I have purchased this one online NEW 850 WATT 850W DUAL 80MM FAN SATA ATX PSU QUIET PC 8-PIN POWER SUPPLY UNIT | eBay

I know its a cheap model, but being 850w and giving all the connections I should need I figured the extra 350w will make up for its cheapness and still provide ample power keeping the system stable.

so here's where I come to the problem..

I was gong to install it but as I was about to unplug the 12v atx cable from my mobo I realized its only a 4pin, sitting in an 8pin slot???

here's is my mobo specs GIGABYTE - Motherboard - Socket AM3+ - GA-78LMT-USB3 (rev. 4.1)

so what should I do? should I plug a 4pin connector into the 8pin slot the same as it is now, as I've had no problems with it running like this, or do I plug an 8pin (4+4)into the slot??

I didn't build this system, rather I purchased it from an online custom build shop, the system runs stable, and the bios is at default so know no voltages have been tinkered with. I am new to this side of things and have never installed a psu, I mean everything looks simple enough, its just this one thing, 8pin or 4pin.

I would appreciate any advise that is given.

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current spec
O/S: win7 64bit
HDD: 500gb sata drive
MB: ga-78lmt-usb3 Rev 4.1 (bios F2)
CPU: amd quad core fx4170 black edition 4.2ghz
GPU: asus Radeon 6570 1gb
RAM: Patriot 8gb ddr3 1600mhz x2
PSU: winpower ad-e500ae-a5/a6 500w
-----------------------------------------------------------------------------------------------------
new spec
O/S: win7 64bit
HDD: 500gb sata ddrive
MB: ga-78lmt-usb3 Rev 4.1 (bios F2)
CPU: amd quad core fx4170 black edition 4.2ghz
GPU: VTX Radeon HD7850 1gb pci-e 3.0
RAM: Patriot 8gb ddr3 1600mhz x2
PSU: winpower +plus power supply 850w
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ICIT2LOL · 04 Jul 2013

Hello demon mate such a big no no buying from Ebay mate unless you have dealt with them before and even then there is no way I would. I would have thought a Corsair TX 750 or even a HX 650 would have been a much safer way to go.

You are about to get a flood of advice no doubt but for my money I would have gone the extra mile and got a decent brand I don't know this brand and the thing with the leads I am not sure what or why there is an eight pin socket.

Look sit tight and someone will soon pick up on this and will know what the go is.

Here is a little something I found and it seems that if you are going to run a humongous CPU then you will only need the four pin http://www.tomshardware.com/answers/...tor-power.html

demongorgan · 04 Jul 2013

Thanks for the reply. I agree with you that I prob shouldn't have used eBay, but really didn't have the money to throw at the corsier (I wish I did) what I spent was every last penny until I get paid next month. Just needed something to get me up and running again really.

Thanks again for the reply.
Dave

ICIT2LOL · 04 Jul 2013

Sorry Dave didn't mean to make you feel bad mate all us old fellas have been there done that. I think you can go with that one you got as I said the eight pin set up is for power munching CPU's and I don't know of many around that would gobble the power up from that sort of supply (ATX)

Just out of interest just what does the sticker on the side say re the +12v rail/s - in amps as you can work out the watts from those two figures and then it is just a matter of finding out the power consumption of the heardware. Now in days not long past CPUs would chew power up but I must have a look at what you have got to see what it uses max.

AMD FX-8350 8 Core Black Edition Processor uses 125 watts which mean that the +12v must supply approx 10 amps of current I found this for yours http://www.cpu-world.com/CPUs/Bulldozer/AMD-FX-Series%20FX-4170%20FD4170FRW4KGU.html so it will need the similar amount of current.

Mind you you haven't mentioned cooling yet are you getting an after market cooler mate as I think it might be a wise move with the AMD puppy.

demongorgan · 04 Jul 2013

Hi again mate :)

naa its ok, I agree with you, shoulda braught better just lack of cash at the mo, will be upgrading to the CX after saving up for bit to get it. I havnt got an after market cooler yet, but when I get the corsier I will prob get myself a nice one. the sticker on the side shows the following:

+3+3v=24A, +5v=30A, +12v1=34A. +12v2=34A, +12v3=34A, +12v4=34A, -12v=0.5A, +5Vsb=3.0A

Thanks for the help and reply
Dave

ICIT2LOL · 04 Jul 2013

Ok Dave now just for keeping in mind have a rummage through this lot

Corsair Power Supply Units

I have the HX 650 in my Sandy Bridge mind you I don't give it any stick and the HX 1050 in the Ivy bridge again it doesn't get a hiding but both are more than capable of supplying heaps of grunt when you want it. Worth keeping your eye out for clearance sales on these units (Corsair) they are quiet and well made. The big one I got when they upgraded to the next 1050.

In the meantime give that one a burl the least it can do is not provide enough power to start the machine up. Strange config of rails though usually you see one or two max +12v but four hum you sure you got that right cos 12v x 34 amps is 408 watts. In Ohms law you multiply the volts by the amps to get the watts:)

demongorgan · 04 Jul 2013

Yep that's deff what the label said. So I plug in both 4pins to make an 8pin? Even though my 500w atm only using a 4pin? Just want to make sure I'm right first time so as not to damage something.

Thanks again.
Dave

ICIT2LOL · 04 Jul 2013

Hiyya Dave sorry late reply mate - lie in this morning :) Well what I would try is just one plug in and see if the machine works if those cables start getting a tad hot then plug in the other. I don't remember seeing an eight pin set up and frankly cannot see why there is such a thing. Most boards I have had had just the one four pin set up.

Did you try asking the dealer you bought the board from too?

The other solution is to contact Gigabyte of course but that is a work of art mate I know from past experience the want the board version every ruddy number and wherewithal you can poke a stick at and they are not known for being quick off the mark with their replies

I am surprised no one else has made a comment I'll ask my mate he is fairly cluey ok?

Any chance of a pic of that label mate please?

Britton30 · 04 Jul 2013

Some boards have a 8 pin connector, it's called EPS12V (Extended Power Supply), which are designed to take 4 OR 8 pin cables. It should work either way but if you have the 4+4 pin connector, use all 8. It supplies the CPU volt regulator mainly.
The ATX connector is the main power connector, 20/24 pin and some boards will accept either of those too.

Having said that, you may not be getting a good PSU even if it is rated high. IT likely has no active power correction or good regulator and may supply "dirty" power, fluctuating volts and current. While it's a few quid more the Corsairs are good ones along with Antec and Seasonic. A poor PSU could damage other components as well.

ICIT2LOL · 04 Jul 2013

Thanks G I knew you would know about this feature just haven't come across it before:)