GTX260 Black Edition SLI issue

[flaming-ninja]

Hello,

I recently updated my PC with an Intel Core i7 2600K on an MSI P67A-GD65 (B3) Motherboard.
I placed a second XFX GTX260 Black Edition Graphics Card next to my first one to do some SLI (First Time Experiencing SLI).
I'm running Windows 7 x64 (Service Pack 1) and my PSU is a CoolerMaster RealPower M620.
The PSU has two PCIe 6-PIN connectors, each connected to another Graphics Card.
I made the other two PCIe 6-PIN Connectors with two 2 molex-> 1 PCIe 6-PIN connectors.
But when I booted my PC it showed just one GTX 260 in the Device Manager!
Installed latest Drivers and everything, but still it's just showing one GTX 260.
Switched Graphics Cards to make sure both are working and they are.
My motherboard (the MSI P67A-GD65 (B3)) has two PCIe 2.0 slots.
The first normally gives a x16 speed with one GPU, and in SLI mode both slots give a x8 speed.
And when I check the BUS speed of the working GTX260 in the NVIDIA Control Panel it shows a x8 speed.
So my first thought was that the PSU would be the problem, by giving not enough power on the 12V rail.
But now comes the, in my opinion, most weird thing about my issue.
Because when I take out the second GPU and connect both 6-PIN PCIe connectors from my PSU directly to the GPU and then boot my PC, I screen stays blank!
The light of my screen stays orange (meaning there's no input signal) .
Now again, when changing the Graphics Cards, both have the same problem.
When I press the Power Button once short, the PC shuts down directly, meaning it doesn't start Windows or anything.
So I cleared the CMOS (Little button on rear IO) but still no input signal on my screen.
I read quite a few forums but that didn't really help till now so I thought let's start one myself, hoping someone can help me...

Thanks in advance!

 

[Mousemonkey]

Where did you get the second card from?

 

[flaming-ninja]

Secondhand, but like I said, when I switch cards same thing happens, only get output from the card in the first slot, not matter which card I use.
And when I use only one card none of both will give an output signal...

 

[Mousemonkey]

Did you see the secondhand card working before you bought it?

 

[flaming-ninja]

No, not in another PC, But I can try it once maybe in my brother's...
But then again, how is it possible I get no input signal on my monitor when only using my own Graphics Card?

 

[Mousemonkey]

I'm wondering if the card faulty and has possibly damaged your motherboard slots, I would only risk trying it another computer if that machine was worthless and you didn't care if it got destroyed.

 

[flaming-ninja]

So you're saying there's no way I can just leave one of the two Graphics Cards out and just use one on x16?

 

[billj214]

Make sure you have power on both cards in all the slots.
6 pin and 8 pin slots all need to have power or the card will not show up.
You also do not want to use any IDE power adapters to run your graphics cards.

 

[Mousemonkey]

Secondhand, but like I said, when I switch cards same thing happens, only get output from the card in the first slot, not matter which card I use.
And when I use only one card none of both will give an output signal...

So you're saying there's no way I can just leave one of the two Graphics Cards out and just use one on x16?

The post you've edited doesn't really make sense, are you getting output from either card or not?

 

[flaming-ninja]

Okay, let's call my own GC "A" and the one I bought second-hand "B".
When I put A in slot 1 and B in slot 2, I get an output signal through A, not through B.
When I put B in slot 1 and A in slot 2, I get an output signal through B, not through A.
When I put A in slot 1 and leave slot 2 blank, I get no output signal through A.
When I put B in slot 1 and leave slot 2 blank, I get no output signal through B.
Using both cards I have them both powered with one 6-PIN and one 2molex->6-PIN
Using one card I have it powered with two 6-PIN PCIe connectors from the PSU.
Hope this brightens things up?

 

[Mousemonkey]

Could be a motherboard issue, is it running the latest BIOS?

 

[flaming-ninja]

Yeah, just updated BIOS from 1.9 to 1.E
Though I gotta admit I haven't tried using one GPU with the new version yet...
You think that could make any changes?
But I did search through de BIOS a bit, but didn't see anything I could change about PCIe setting...
What does happen is when I boot, I see this screen with some information like HDD's, BIOS version etc, and it also says there: PCIe x1 5GB/s
Is this about the PCIe x1 slot or does it mean that only 1 PCIe x16 slot is being used?

 

[billj214]

Your card has an 8 pin power port, it must have 8 pins feeding it with power or the card will not turn on.

 

[flaming-ninja]

Both my cards have two 6-PIN power ports
(http://techgage.com/reviews/xfx/gtx_260_black_edition/xfx_gtx_260_black_edition_03_thumb.jpg)

 

[billj214]

Both my cards have two 6-PIN power ports
(http://techgage.com/reviews/xfx/gtx_260_black_edition/xfx_gtx_260_black_edition_03_thumb.jpg)

Thanks for that clarification, my GTX 280's all have 8 port's, I assumed it was the same.

 

[kd0frg]

how many watts is your power supply? 620 watts? do you have the SLI bridge? although im not sure a SLI bridge is needed for only 2 cards.. are both cards the same brand/model and same bios on the cards?

 

[Mousemonkey]

how many watts is your power supply? 620 watts? do you have the SLI bridge? although im not sure a SLI bridge is needed for only 2 cards.. are both cards the same brand/model and same bios on the cards?

It is, but they don't have to be the same brand/model and same bios they just both have to be GTX260's and I think the 216 core models can be SL'd with 192 core models but I cannot confirm that.

 

[kd0frg]

each of those cards wants about 185 watts probably, thats a bit much for your PSU probably , the intel i7 2600k probably wants what , 125 watts as well? the 2nd gpu might not use a full 185 watts at idle or while its in use , but over all thats prob almost 500 watts since its the reference gtx 260 power use im looking at, the XFX probably uses more then 185 watts. your psu is rated at 516 watts for the 12v rails, so your cuttin it REAL close .. that is probably the problem.. what i would do, is unplug your computer's PSU power cable, wait about 30 seconds, plug it back in, then plug Card A into Slot 1, and use your PSU's 6 pin power connectors, if that doesnt work, try the power connectors you adapted from the molex's .. and see if u get video output, the power draw you put on your psu might of damaged it.. cant say for sure.. its all theory at this point.

 

[flaming-ninja]

@kd0frg indeed, 620 Watts PSU, Do have the SLI bridge connecter, the one that came with the Motherboard. Both cards are XFX GTX260 Black Edition with 216 cores, though the serial number of the first one is GX-260X-AHBF while the other one is GX-260X-AHBA, but that shouldn't be any problem, because a GTX260 with 192 cores can be run in SLI with too with one with 216 cores...
Yeah, that's what I thought too first, it should be the PSU, but I didn't see why I didn't get any output signal when using one. Haven't tried using a molex adapter while using one, thanks for the tip, I'll try it soon.

 

[flaming-ninja]

Okay, I now figured out the difference between the two serial numbers...
The first one ends with an F and the second one ends with an A.
And because the only difference between the two cards is that the first one came with a free copy of Farcry 2 and the second one came with a free copy of Assassin's creed, It would surely make sense the 'F' is for Farcry and the 'A' is for Assassin's creed ^^
But as you said pulled out the powercord at the back of the PSU, exerted the Graphics Cards during the 30 seconds of waiting, Put one card in the PCIe slot the closest to the CPU, used the two 6-PIN connectors and booted, again nothing.
After that using one 6-PIN and one molex adapter, nothing.
And the same story with two molex adapters...
But when I insert them both, put the SLI Bridge between them and only power the first with two 6-PIN connectors so the second is only powered through the bus, I do get an output signal.
I really have no idea how this is possible...
Another thing is that on most forums that discuss problems with SLI not detected, it's most of the time in combination with a Windows 7 64-bit version, could this have any meaning?
And I also read that someone managed to solve the problem of the SLI not being detected by cleaning all the connections somehow with a diamond thing or whatsoever?
Though I must admit I don't have any experience with that, but he said 'grounded' them or something like that till they were shiny again...