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Action_Man
Currently Appearing As
Premium
join:2003-07-22
England

[motherboard] Motherbaord help please ...

The power connector on my motherboard has eight pins, and is described as ATX 12V 2X, but my PSU has a four pin and a six pin connector, the four pin connects ok, will this be sufficient ? ...


psafux
Premium,VIP
join:2005-11-10
kudos:2

1 recommendation

It may or may not work. I have seen many systems with only one 12V leg plugged in and it worked fine and I have seen systems where it wouldn't POST without both legs.

Typically the 4pin or dual 4pin plug provides power to the CPU so you may have poor performance if the correct power isn't there when it's needed.

The 6 pin connector is (likely) for a video card. It is not compatible with the 12V 4/8 pin slot. Don't even try to jam it in, the molding should prevent it from going it but don't force it. You could fry the board and/or possibly the CPU if you get that in there & fire it up.


Freddy
Premium
join:2005-05-17
Arlington, VA
kudos:2
reply to Action_Man
You can find all kinds of adapters for converting 4-pin to 6-pin or to 8-pin connections, like some of these:

»www.google.com/search?q=4+to+6+p···&bih=710

Look around to find an adapter to fit your needs.

Freddy


koitsu
Premium,MVM
join:2002-07-16
Mountain View, CA
kudos:23
reply to Action_Man
What psafux See Profile says here is correct.

The only counterpoint (sort of) I'd make is that if the motherboard CPU 12V connector is 2x4 (meaning 8 pins) then you should absolutely have a PSU that provides 2x4. You don't know how the motherboard manufacturer chose to distribute power trace-wise across the board; meaning, there's a reason the socket is 2x4 and not 1x4.

Yes, it is possible to plug in only "one leg" of (e.g. one 1x4 header only) and get a functioning system, but I have seem both consumer and server-grade boards misbehave when this happens. For example on one Supermicro system I had, the system would POST but then would begin to behave very strangely shortly thereafter (timecounter began behaving very strangely, and I began seeing bizarre behaviour pertaining to CPU power-saving modes and EIST); issue was 100% reproducible. Upgrading to a PSU that provided a native 2x4 connection solved all those problems. I later found a clause in the motherboard user manual that explicitly said something to the effect of "despite 1x4 working, don't do it, system instability may happen". So when you ask "will it be sufficient?" the answer is "possibly but then again possibly not".

If you're not sure if the board "truly" can work in this fashion, then contact the motherboard manufacturer or check the user manual. Never be afraid to talk to the motherboard manufacturer / technical support folks about questions like this!

Overall though, upgrading your PSU to one that offers 2x8 is probably the best choice overall. Most PSUs today allow for their 2x8 connector to actually be split in half so you end up with two 1x4 connectors (for systems which only have a 1x4 CPU 12V header).
--
Making life hard for others since 1977.
I speak for myself and not my employer/affiliates of my employer.


koitsu
Premium,MVM
join:2002-07-16
Mountain View, CA
kudos:23
reply to Freddy
said by Freddy:

You can find all kinds of adapters for converting 4-pin to 6-pin connections, like some of these:

»www.google.com/search?q=4+to+6+p···&bih=710

Look around to find an adapter to fit your needs.

Freddy

Those are molex-to-PCIe power connectors -- that isn't what he's talking about. He's talking about the 12V CPU power connector. Specifically these:

1x4 (4-pin): »www.celtnet.org.uk/images/cpu_power.gif
2x4 (8-pin): »cdnsupport.gateway.com/s/Servers···7305.jpg
--
Making life hard for others since 1977.
I speak for myself and not my employer/affiliates of my employer.


Freddy
Premium
join:2005-05-17
Arlington, VA
kudos:2
I think one can find all sorts of power adapters, such as those original poster needs, example:

»www.amazon.com/s/?ie=UTF8&keywor···gib152_b

I was only trying to provide some ideas for looking around. There are many adapters available.

Freddy


koitsu
Premium,MVM
join:2002-07-16
Mountain View, CA
kudos:23
These could work for him, but they don't solve the actual power/load distribution concerns (depends on how the PSU is manufactured):

»www.amazon.com/StarTech-6in-Pin-···02O21XHQ
»www.amazon.com/HDE-8-Pin-Power-4···02BFNZAO
»www.amazon.com/Male-Female-Power···05L90Q0O

There is one type of cable/adapter that I strongly recommend you DO NOT USE:

»www.amazon.com/Micro-SATA-Cables···f=sr_1_7

This is a very, very dangerous cable to use. Let me explain: more often than not, the 12V CPU "rails" (for lack of better term) tend to be much more strict/precise (better designed, circuitry-wise inside of the PSU) than the 12V used on standard 4-pin Molex. The "rails" used for the 12V Molex connectors tend to have massive amounts of variance -- I've seen from 11.8V all the way up to 12.3V. Proof (and this is on a server-class board):

root@icarus:/root # bsdhwmon
CPU1 Temperature           33 C
System Temperature         37 C
FAN1                        0 RPM
FAN2                        0 RPM
FAN3                        0 RPM
FAN4                     2042 RPM
FAN5                        0 RPM
FAN6                     1875 RPM
VcoreA                  1.106 V
MCH Core                1.522 V
-12V                  -12.288 V
V_DIMM                  1.712 V
+3.3V                   3.392 V
+12V                   12.096 V
5Vsb                    5.070 V
5VDD                    5.118 V
P_VTT                   1.142 V
Vbat                    3.328 V
 

The 12V coming in for a CPU tends to have much more stringent requirements. So please, do not use Molex-to-CPU-power-connector adapters!

Edit: someone may want to verify for me which 12V type the Molex connector use, either +12V or -12V (yes it matters). I can't remember.

Finally: the OP is also in the UK/GB so these exact products may or may not be available at UK Amazon.

--
Making life hard for others since 1977.
I speak for myself and not my employer/affiliates of my employer.


Action_Man
Currently Appearing As
Premium
join:2003-07-22
England
reply to Action_Man
It probably wont make a great deal of difference in this instance, but i will post my specs :-

GIGABYTE - Motherboard - Socket 775 - GA-X48-DS4 (rev. 1.3)

ARK | Intel® Pentium® Processor E5200 (2M Cache, 2.50 GHz, 800 MHz FSB) - (I also have an E5300)

I have tried powering up with just the four pin connected, but it powers straight down, then keeps resetting itself, so I will go and purchase a new PSU tomorrow.

Thanks for all the information, much appreciated ...



n_w95482
Premium
join:2005-08-03
Ukiah, CA
reply to koitsu
said by koitsu:

Edit: someone may want to verify for me which 12V type the Molex connector use, either +12V or -12V (yes it matters). I can't remember.

It's +12v. As far as I know, -5 (old ATX)/-12 are only provided by the ATX connector and are only used for legacy reasons (ex. RS-232, ISA).

ATX 2.0 mandated the split-rail system that is common nowadays, but 2.3 removed that requirement. Newer power supplies are trending towards one big 12v rail. Hopefully that results in consistent regulation on all 12v-carrying connectors.
--
KI6RIT


koitsu
Premium,MVM
join:2002-07-16
Mountain View, CA
kudos:23
Thanks n_w95482 See Profile, sounds like my concern over the 12V bits is unjustified then. (I'm happy to be wrong )

The only concern I have about one big 12V rail is with regards to the devices which connect via 4-pin Molex. I'd need an EE person around to verify but as I remember a lot of consumer devices tended to be "noisy" or make a mess of the electrical, which is why they were segregated from other 12V lines. Possibly that has changed with ATX revision improvements (I don't follow those -- my brain is full!) and vendors are better about it now.

I do remember the whole single rail vs. multiple rail argument, which resulted in a bunch of hullabaloo over "everyone needing multiple rails", then 3-4 years later there's a whole "single rail" movement. I wish people would be consistent.
--
Making life hard for others since 1977.
I speak for myself and not my employer/affiliates of my employer.


koitsu
Premium,MVM
join:2002-07-16
Mountain View, CA
kudos:23
reply to Action_Man
Behaviour described could be one of 4 things as I see it:

1. PSU needing to provide 2x8 12V power like we've talked about,
2. CPU model or revision (stepping) not supported by the BIOS (result: immediately shuts off power). Sometimes BIOS updates (which provide newer microcode) can fix this but only the MB vendor would know. If Gigabyte says that exact model and stepping of CPU is supposed on that board with your BIOS version then you're good, otherwise contact Gigabyte and they might be able to update the BIOS for you (you'd need to send you board to them),
3. Some kind of actual motherboard problem, such as blown caps or faulty VRMs. This sounds extremely unlikely though, as the caps on Gigabyte boards tend to be solid; the first two possibilities are much more likely, and finally,
4. Bad CPU -- extremely unlikely on many levels but is always a possibility to some degree.
--
Making life hard for others since 1977.
I speak for myself and not my employer/affiliates of my employer.


Action_Man
Currently Appearing As
Premium
join:2003-07-22
England
reply to Action_Man
Looking at the cpu support list, it may not work with an early bios, so i will get the psu and test that, if that fails, then i may have to get an older cpu to update the bios ...

n_w95482
Premium
join:2005-08-03
Ukiah, CA

1 recommendation

reply to koitsu
I think part of the split-rail movement was that there were safety concerns about allowing so much current over a single rail. The problem then moved over to crossloading issues with split rails, since power supplies rarely documented what cables ran off of which rail. Additional filtering could be part of the 2.3 spec, but I have no idea.
--
KI6RIT


FizzyMyNizzy

join:2004-05-29
New York, NY

4 edits
reply to Action_Man
Click for full size
The 8 pin that is on your mainboard is called EPS12V. The wiring is different than pcie 8pin. You do not want to force it in.

Most older psu does have one or two 4 pin. Make sure the sharp match and the release tab is on the right place.

Pcie and eps12v have different sharp.

4pin out of the 8Pin with that cpu, is enough. It will boot-up and should work fine. Some mainboard manufacture have a cap that cover up 4pin on the 8pin.

exp:



Intel® Pentium® Processor E5200
(2M Cache, 2.50 GHz, 800 MHz FSB)
65W
»ark.intel.com/products/37212/Int···-MHz-FSB


Action_Man
Currently Appearing As
Premium
join:2003-07-22
England
I cant do anything with it until my new processor arrives, as i need an older cpu to update the bios ...


Action_Man
Currently Appearing As
Premium
join:2003-07-22
England
I have got it up and running after using an old CPU so i could update the bios, every things working fine, except for the video card, which is giving a blue screen after installing the driver, which was recommended for my OS, but i have another video card to use, so all is good, thank you .

But if anyone wants to help me with the video card, i would be grateful .

The Mobo is GA-X48-DS4
The Graphics card is Inno3D GF 9500 GT 1GB
The OS is Windows 7 32bit
The driver is 306.97-desktop-win8-win7-winvista-32bit-english-whql

If i need to give any more details, let me know ...

n_w95482
Premium
join:2005-08-03
Ukiah, CA
Try an older driver, like the 296.10.
--
KI6RIT


Action_Man
Currently Appearing As
Premium
join:2003-07-22
England
Tried that driver, still the same i`m afraid, its not important as i have a couple more cards which i can use, thanks for the help ...