The 2x4 pin CPU power connector on my mobo.

[Dankk]

Here is my dilemma: For my new computer, I am getting an AMD Phenom II X4 955 Deneb 3.2GHz processor, which is a quad core. My motherboard - which is a GIGABYTE GA-MA770T-UD3P - has a 2x4 pin power connector for the processor. However, my power supply only has the 2x2 pin connector.

So... 2x4pin versus 2x2pin. How will this work?

I read that for most setups, if your motherboard has the 2x4 but your PSU only has 2x2, then you just plug the 2x2 into the right side of the motherboard port and it works fine (you don't need to use all 8 pins). However, I ALSO read that the reason for the 2x4pin jack is specifically for quad cores.

If I wasn't using a quadcore processor, I would feel OK about this, but since I am, I'm not so sure. With the AMD processor mentioned above, would it be fine if I only used half of the 2x4 power jack on my motherboard? Or will this not be enough?

I also find it interesting that some of the other AM3 motherboards only have the 2x2 connector. It's as if some motherboards need the extra four pins, whereas others don't. I just want to know if my computer will be fine if I use only four of the eight pins with my particular CPU. Thanks.

(For the record, I am using 20+4 pin for the main motherboard power. I don't know if this makes a difference or not, but just in case.)

 

[Jd007]

Using the 4-pin CPU connector should be fine. Just don't OC or increase your VCore.

 

[TemjinGold]

Are you sure you don't have it? I ask because my HX520 has it so it seems strange for your 650w Corsair not to...

 

[Dankk]

Are you sure you don't have it? I ask because my HX520 has it so it seems strange for your 650w Corsair not to...

I'm talking about the computer I'm going eventually buy, not the one I currently have.

Using the 4-pin CPU connector should be fine. Just don't OC or increase your VCore.

I don't plan on overclocking this one.

 

[ShawnD1]

Using the 4-pin CPU connector should be fine. Just don't OC or increase your VCore.

I think it also matters where you put the 4-pin. My motherboard's instruction manual explicitly states that a single 4-pin must go in the left 4 slots.

That's how I have mine and it seems to work. 4-pin in the left 4 slots, the other 4 slots don't have anything connected. The computer successfully passes Prime95 as well as OCCT's PSU test. OCCT's graphs were showing incredibly high voltage ripple, which I thought may have been caused by not having enough power, but the ripple went away completely when I added a UPS.

 

[Dankk]

I think it also matters where you put the 4-pin. My motherboard's instruction manual explicitly states that a single 4-pin must go in the left 4 slots.

I am fully aware of this. I have already looked at the motherboard manual and I can see which pins I am supposed to use.

That's how I have mine and it seems to work. 4-pin in the left 4 slots, the other 4 slots don't have anything connected. The computer successfully passes Prime95 as well as OCCT's PSU test. OCCT's graphs were showing incredibly high voltage ripple, which I thought may have been caused by not having enough power, but the ripple went away completely when I added a UPS.

Sounds good, although keep in mind the kind of processor I am going to be using. It's an AMD Phenom II x4 quad core, which I imagine is beefier than most other CPUs for that socket.

Edit: I've never heard the term "UPS" before, so I looked it up. How do I know if I have an uninterruptable power supply? Or, what exactly is one?

 

[zagood]

A UPS is a separate piece of hardware that (temporarily) maintains system power in the event of a power failure from the wall.
http://www.google.com/products?hl=e...R2GGLL_enUS361&aql=&um=1&ie=UTF-8&sa=N&tab=wf

 

[Ben90]

IIRC the 2x2 power connector will only fit one way.

A UPS (or is it an UPS cuz that just sounds weird) is basically an array of batteries. Normally used in the enterprise market to make sure the datacenters are running 24/7 they normally consist of huge battery banks and generators to power them in case the power goes out.

On the consumer side a UPS is basically just a big battery in between the wall and computer's PSU that works like this:

I wouldn't worry about it though unless you need absolute 24/7 run time

 

[Dankk]

Thanks for telling me about what a UPS is, zagood and Ben90. I was wondering if one of these was actually necessary to prevent the "voltage ripple" ShawnD1 was talking about, but maybe not?

So far it looks like I'm probably in the clear, but because I'm paranoid about this sort of thing I want to make sure that using this type of a power connection will work fine with an AMD Phenom II x4 Deneb. Thanks.

 

[Aluvus]

I read that for most setups, if your motherboard has the 2x4 but your PSU only has 2x2, then you just plug the 2x2 into the right side of the motherboard port and it works fine (you don't need to use all 8 pins). However, I ALSO read that the reason for the 2x4pin jack is specifically for quad cores.

The 8-pin connector exists to better support CPUs that draw a lot of power, many of which happen to be quad-core.

I also find it interesting that some of the other AM3 motherboards only have the 2x2 connector. It's as if some motherboards need the extra four pins, whereas others don't.

Without doing any real research, I would expect that cheaper motherboards are generally more likely to use the 4-pin connector. The motherboard manufacturers can reasonably assume that most people buying those boards will be using them with cheaper (thus lower-performance, thus lower-power) CPUs.

A few years ago it was the case that many cheaper motherboards had cheaply-designed power systems that could not handle high-power CPUs (the motherboard regulates +12 V down to whatever the processor needs).

I just want to know if my computer will be fine if I use only four of the eight pins with my particular CPU. Thanks.

My expectation would be that it would work fine. However, if it were my system, I would be shopping for a good deal on a power supply. Your chosen CPU with a Thermal Design Power of 125 W is certainly on the upper end of the spectrum for socket AM3, but then it's also about on par with a Pentium 4 Prescott.

Thanks for telling me about what a UPS is, zagood and Ben90. I was wondering if one of these was actually necessary to prevent the "voltage ripple" ShawnD1 was talking about, but maybe not?

Unless you are buying a relatively high-dollar UPS, it should have no major effect on the power going into the PSU except when the mains supply goes down and it has to start running from its battery (and at that point it will most likely make life worse for the PSU). I would be extremely skeptical of any power supply measurement done by software.

 

[Dankk]

Thank you Aluvus, that is a very informative and helpful post.

I am stingy about changing the power supply, because the one I'm planning on getting is already built into this Raidmax Smilodon case. Also, I think I'm going to use this 12v 4 pin to 8 pin adapter. Although we know it's probably not going to actually provide more power, it's certainly not going to hurt anything either.

If anyone has any additional insight on this then let me know. Otherwise, with these things in mind, I think I just might spring for it.

 

[Markfw]

Just to let you know... I just bought a raidmax case for $20, that came with a 380 watt psu. I actually threw it in the garbage without ever firing it up, since I knew it was crap (weight was teltale). I didn't want one of my systems to self-implode with a crap psu.

I have no idea what this case has, just passing info along.....My raidmax was CRAP !!!

 

[Dankk]

I have no idea what this case has, just passing info along.....

If you look at the Newegg product page, it has a 5/5 rating with 1,472 reviews and has been one of the top bestselling cases on Newegg for as long as I can remember.

I've never used it personally before but I'm going off of comments from people who have actually purchased and built with it.

 

[VirtualLarry]

Yeah, building with a Raidmax PSU is just asking for trouble.

 

[TemjinGold]

If you look at the Newegg product page, it has a 5/5 rating with 1,472 reviews and has been one of the top bestselling cases on Newegg for as long as I can remember.

I've never used it personally before but I'm going off of comments from people who have actually purchased and built with it.

While that's true, if you read those comments, you'll see just how uninformed the average Newegg reviewer is.

Keep in mind, a lot of people are simply too cheap to buy something good. I have a friend like that who buys the cheapest thing he can find possible for anything, regardless of quality. He plugs it in and if it works fine so far, he sees no point in getting something better. That PSU is really cheap, which is likely the reason for most of those 5/5 reviews.

 

[Dankk]

Perhaps I will look for some good combo deals on a case and power supply.

Thanks for the input.

 

[Markfw]

Uour case is fine. Why not get one of these for $40

http://www.svc.com/ocz700gxssli-b.html

(I have 4 of them)

 

[Occ]

I'm currently doing this with a x3 720 with the 4th core unlocked. Mobo has 8 pin cpu power plug, 650 watt cooler master power supply has a 4 pin chord. got a converter from 4 to 8 from newegg and it works. you probably dont need one, but theyre not that expensive. one thing though, my post times are pretty long, i think thats the reason. once it posts it comes up nice and quick though. been running it for a couple months now and have experienced no problems.