Nvidia 580 GTX problem

[oggmeista]

Am having major problems trying to fire up my newly built system and thought it might be best to tackle each of my issues seprately so this is the first question I need to ask

With the Nvidia 580 gtx or probably any of the Nvidia GFX cards

It has 2 plug in sockets an 8 pin and a 6 pin PEGI molex sockets

Visiting 2 different forums a cam back with contrasting answers

In 1 forum it was suggested I can use either cable
Whilst in the other (NVidia) forum people were adement that you should use both cables

The problem is that when at first I plugged in both the cables the machine would not even boot up
However when I just connected the 6 pin cable the machine starts up and I see the fans on the card spinning, but the monitor does not come on

So which is the right method either one or both together?

plz I really need some help with this

thx

 

[thefogo]

Yes you need to use both cables.
What PSU do you have?

 

[panyan]

Yes you need to use both cables.

+1 important

What PSU do you have?

+1 even more important

 

[oggmeista]

Hi thx for answering guys

Ok well that is one little query taken care of, I have a Tagan T900 non modular PSU

So if the machine is not booting with both connectors plugged in (and the monitor not turning on) Is that a an almost certain indicator that the problem is the GFX card?

Should probably add here that I have also installed a non stadard cooler (Arctic freezer pro 7 rev 2) but it is not spinning at all, was told this was sometimes caused by the system itself I should probably also add that this system has 7 chassis fans all working

What would you suggest to be the best solution for my problem?

thx again

 

[thefogo]

I think you will need a new power supply mate. Never heard of that brand and I can't find anything on it, so I doubt it's any good.

 

[oggmeista]

Thx for you opinion

Going to check if the system will boot if I just use the 8 pin cable...



http://www.youtube.com/watch?v=7g4XcTKnXw8

 

[thefogo]

From the specs the psu doesn't have an 8 pin pci-e cable?

 

[rtho782]

Thx for you opinion

Going to check if the system will boot if I just use the 8 pin cable...



http://www.youtube.com/watch?v=7g4XcTKnXw8

No.

You need to use both cables. Otherwise you are proposing drawing 225W, or 18.75A, over 1 cable.

That's 6.25A per 12v pin on the 8pin connector (only 3 are +12v.)

Your chances of a melted cable are high. If it's 20AWG cable, the safe limit is 5A. Even 18AWG it's 7Amps.

Don't do this. It is wrong. Why would the gpu come with two connectors if it only needed one.

Your system already didn't boot with 1 connector. This is because the GPU was not getting enough power, and/or protection circuitry kicked in and stopped the GPU working as it knew only one connector was in.

It probably didn't come on at all with both in as you probably had both on the same rail. Your PSU has 4 20A rails, both these connectors on one rail means 18.75A, so if anything else is on the same rail it won't boot.

Why ask for help if you won't listen to people :/

 

[Deceptor]

Had a Tagan PSU before, to say it's **** is an understatement.

 

[oggmeista]

No.

You need to use both cables. Otherwise you are proposing drawing 225W, or 18.75A, over 1 cable.

That's 6.25A per 12v pin on the 8pin connector (only 3 are +12v.)

Your chances of a melted cable are high. If it's 20AWG cable, the safe limit is 5A. Even 18AWG it's 7Amps.

Don't do this. It is wrong. Why would the gpu come with two connectors if it only needed one.

Your system already didn't boot with 1 connector. This is because the GPU was not getting enough power, and/or protection circuitry kicked in and stopped the GPU working as it knew only one connector was in.

It probably didn't come on at all with both in as you probably had both on the same rail. Your PSU has 4 20A rails, both these connectors on one rail means 18.75A, so if anything else is on the same rail it won't boot.

Why ask for help if you won't listen to people :/

Bro no offense I am listening to people, just trying to understand what is causing what by deduction, and with feedback and advice, after all people were giving different advicce in another forum and were even highlighting it with diagrams so I have to do my research

however, Hmm strange, right ok I got the fan working now, but the monitor is still not coming on, yes I am using 2x PCI-E cables as you have strongly advised, It's not making any beeping noises ie POST because it seems the Post motherboard internal speaker is missing from my package, I will have this installed very soon though card fans are spinning, but there is no response from my monitor
I am pretty sure the monitor is connected correctly (ACER)
GFX card?

You might like to look at this though

http://www.overclock.net/a/gpu-and-cpu-power-connections ie (power connectors section)

 

[oggmeista]

Had a Tagan PSU before, to say it's **** is an understatement.

Funny everywhere I look they get highly rated maybe yours had manufacturing defects or faults, doesn't disguise the media critical acclaim of the majority of their products, and conversely yours is brilliant of course because it has served you well, Well I'd rather prefer to stick to the facts....

 

[rtho782]

You might like to look at this though

http://www.overclock.net/a/gpu-and-cpu-power-connections ie (power connectors section)

I'm not sure what relevance a random article written by who knows who with zero references is supposed to have, but even that doesn't say you only need one of the connectors.

It does say you probably don't need to connect the molex connector on the motherboard (for a motherboard that has such a connector) if you have a GPU with PCIe power connectors.

This is a molex connector: http://upload.wikimedia.org/wikipedia/commons/1/1e/Molex_male_connector.jpg

Some motherboards have one of these on the board, it is not talking about connectors on the GPU.

It also says that the 6pin and 8pin PCIe power connectors are rated for 80W and 120W respectively. This is wrong. Categorically wrong.

From Wikipedia PCI Express article, power section, 2nd paragraph:
Optional connectors add 75 W (6-pin) or 150 W (8-pin) power for up to 300 W total (2×75 W + 1×150 W).

Given that the article you have linked makes such basic mistakes I don't really trust it, but I don't actually see where it disagrees with anything I've said other than the above mentioned bit. Oh, except that it says "you could plug a 6 pin connector in offset to an 8 pin socket". No, plugging it in to one side of the socket and the sense pin won't connect and it won't work. To get it in on the other side of the socket, you'd have to modify the plug with a knife, and you'd be putting +12v up a sense pin. Bad idea.

You are self evidently assembling a computer from old/second hand parts, it may well be that something is broken?

Are you using PCIe to molex Y connectors, or does the PSU have 6pin and 8pin PCIe power connectors?

I still think it's either rail distribution on the PSU (4x20A rails, if you have everything on one or two rails it's tripping overcurrent protection) or a duff gpu.

 

[Supernaut91]

Bro no offense I am listening to people, just trying to understand what is causing what by deduction, and with feedback and advice, after all people were giving different advicce in another forum and were even highlighting it with diagrams so I have to do my research

however, Hmm strange, right ok I got the fan working now, but the monitor is still not coming on, yes I am using 2x PCI-E cables as you have strongly advised, It's not making any beeping noises ie POST because it seems the Post motherboard internal speaker is missing from my package, I will have this installed very soon though card fans are spinning, but there is no response from my monitor
I am pretty sure the monitor is connected correctly (ACER)
GFX card?

You might like to look at this though

http://www.overclock.net/a/gpu-and-cpu-power-connections ie (power connectors section)

Take it to a local computer shop before you damage the components even further, you are clearly inexperienced. Playing with computer hardware may seem just like Lego, but you need to either do a little bit more research or have someone teach you.