GA-H55M-USB3 IH55 8 pin ATX connector?

[Wlibri]

I wish to build a new PC to suite my requirements and have decided to utilise an Intel i5 650 -1156 processor/Gigabyte H55M-USB3 IH55 motherboard combination as my main platform.

On reviewing the motherboard specs, I have discovered that it is equiped with a 8 Pin ATX 12v power connector (something new to me as I am used to a 4 Pin connector). The PSU I have elected to use is equipped with a 4-Pin socket.

Question:

1) What is the purpose of the 8-Pins? and
2) Is it possible to connect a 4-Pin socket to one side leaving the other 4 pins exposed ?

I look foreward to your reply.

[Dark Mantis]

Hi and welcome to the Gigabyte Forum.

You really do need to use all 8 pins of the connector. This however isn't a problem as you can use an adapter if your PSU doesn't come with the required plugs. I would suggest that you post your make/model of PSU here for advice on it's suitability.

[Wlibri]

Thank you for your prompt response.

The PSU I plan to use is a Seasonic SS-400ES 400W ATX PSU (80 plus compliant).
This has been reccommended to me by an associate and it is not cheap.
I reside in South Africa where unfortunately it is not locally available way and I need to order it through an online supplier some 600 Km away.
Been onto the4 web site and found the information is limited i.e. no mention of the connectors supplied.
I hope that this will suffice?

[Wlibri]

Whilst I am waiting for your reply to PSU information forweded to you in my last message, my I return to my original question. What is the purpose of the 8 Pin  ATX socket as this is something new to me.
To which you replied "You really do need to use all 8 pins of the connector. This however isn't a problem as you can use an adapter if your PSU doesn't come with the required plugs."

So in the mean time I have deduced that the additional 4 Pins are intended to supply additional current for overclocking?
The reason I state this this is that the CPU's TDP (Maximum power before thermal dissipation overload.) is around 73W. (http://ark.intel.com/Product.aspx?id=43546) and a 4-pin ATX 12V power connector should provide 75W on it's own comfortably without getting warm or anything and that's in addition to the 3.3V supply that the CPU already gets via the dedicated PSU outputs which amounts to a maximum of around 100W.
So although there is an 8-pin connector on the motherboard and although the BIOS of the board may require to sense some voltage there in order to power up the CPU, the actual drain on that connector I expect will be minimal if any at all.

I look forward to your reply

[absic]

Hi there,

You are correct insofar as you probably will be able to run your choice of CPU with only the 4 pin connector attached. However, using an 8 pin connector offers greater system stability and is not just for when you overclock.

The User's Manual for your choice of motherboard states:

Use of a power supply providing a 2x4 12V power connector is recommended by the CPU manufacturer when using an Intel Extreme Edition CPU (130W).
To meet expansion requirements, it is recommended that a power supply that can withstand high power consumption be used (500W or greater). If a power supply is used that does not provide the required power, the result can lead to an unstable or unbootable system.

So your choice of a 400 Watt PSU isn't recommended by Gigabyte. However, if you decide to stick with your choice of PSU and it only has a 4 pin connector you can plug it into the 8 pin socket using pins 3, 4, 5 & 8 leaving the others open and your system should work.

As DM has stated though, you can also by a cheap 4 pin to 8 Pin converter which will allow you to use all 8 pins on the motherboard and also provide the extra power for improved system stability

[Dark Mantis]

The EPS connector also supplies additional power to the PCIE slots. If you could post your components that you are planning to run off this PSU I would have a better idea of whether it will even be powerful enough.

[Wlibri]

Hello Dark Mantis

I have attached complete list of components and software I will be using.
This is a chance that I could attach a GPU later depending on the definition I obtian from the on board graphics.
The attachment includes my complete system file which comprises a pdf copy? Are you able to open and ifnow how do a attach the PDF copy only?

[Dark Mantis]

I hope the prices are in Rand! I nearly had a heart attack when I first saw them and thought it was Pounds.

Looks fine apart from the PSU. Good make but to little power, especially if you wanted to add anything let alone a GPU. I don't know what you are intending to use this for apart from the programs that you listed but if your grap[hics requirements are fairly steep then I would advise looking more for roughly 650W and preferably a single 12V rail. Seasonic, Corsair, Enermax, Gigabyte etc.

[Wlibri]

Thank you for your reply.

Your comments make sense. I will go for your suggested 650W PSU and modify with a 4 Pin to 8 pin converter. This still seems very large for my application. I am preesently running a 8 year old Pentium 4 775 based sustem with 1 GB DDR2 400 RAM, 2 x 80 GB HDDS and a small  GPU which is equiped with all WIN XP Professional OS, Office 2003 Professional, MS Project 2000 and AutoCad 2007 and I do not experience any problems other than the system being a bit slow.

Incidentally, have you come across the EZCOOL brand of PSU in the UK?
My original 300w PSU packed up about 3 years ago and I replaced this with a Codegen Dual +12V unit which lasted exactly 14 months.
It was over a weekend when most reputable computer suppliers are closed, so I managed to obtain a CZCOOL 450W PSU from an unknown supplier for R199.00.
This is a very quiet running unit and has successfully provided very good service over the past 3 years.
The only problem being that it only offers a single wire harness whereas all the previous PSUs I have had have 2 harnesses
I look forward to your comments

[Dark Mantis]

If the  PSU is three years old it has gone past it's useful stage anyway. They deteriorate in power and reliability over time especailly the older models. It would have lost about 10-15% probably of it's output. A good quality modern one should last twice as long and not drop in output so much.

I can't say I have come across this particular brand but there are so many cheap and chearful ones on the market that it is not surprising. The trouble is when they go wrong they can take out half you computer components with them.

[Wlibri]

Thank you for your reply regarding the failure of PSUs and yes agree that it would be wise to steer clear of the cheapies.
Will definately go for a reputable make.

With respect, you do not seem to have responded to my  opening paragraph when I questioned I questioned your recommendation to go for a 650W PSU and followed this up with an example of my present system which is sucessfully operating with a 450W PSU.
Possibly the previous  300W Codegen unit failed prematurely as the result of overload. Who knows!
So I again pose the question: Why go 650W when the present system is comfortably running 450W?

[Dark Mantis]

So I again pose the question: Why go 650W when the present system is comfortably running 450W?

Well I guess I will have to answer you this time then!

For several reasons it makes more sense to go for a slightly larger PSU in the first place.

PSUs work best at roughly 60% power levels so to get that an oversize PSU is best.

It means that over several years the capacitor droop that is the main cause of power drop in PSUs won't have so much effect.

All power supplies only use the amount of power they need so it costs no more(approx) to run a large one as a small one.

Gives extra room for upgrading without having to worry about changing PSU.

Initail cost of a larger PSU is not that much more than a small PSU.

I don't really think I need to go on do I ?

 

[Wlibri]

Thank you for spending so much time to assist me.
I am now well aware of the reasons for going to an 8 pin ATX connector and also accept your reasoning for selecting a larger powered PSU.
As regards your closing sentance,shall we agree on a hapy medium here? That being a the selection of a Gigabyte Odin 585 GE-P585A-C2 Power Supply - 585W.
Reason is price:
The 585 W Gigabyte retails for R501.00 whilst the 650W PSU's start at R1258 - Corsair.
Many thanke once again for the time and effort you have gone to to resolve my concerns.

Oh by the way, the Gigabyte PSU is supplied with 4+4-pin +12V CPU Connector.

Look forward to participating on this forum once I have completed my computer.

[Dark Mantis]

The extra connector was another reason to buy a larger  device. Yes that seems to be a good compromise and I am glad to see that you could get a Gigabyte PSU there. They are a bit hard to come by in our country. I have a 1200W one the Gigabyte Odin Pro 1200 and it is a beast! Beautifully built and really solid.


Look forward to seeing you more often on the forum.