Dual GPU problem! One card is MIA!

[Sacred]

Hi Guys,

I'm at a friends house and have just been testing the FFXIV benchmark on his machine. Anyway long story short the results were quite poor, my friend assured me that the computer had two GPUs in SLi so it should get better results.

I tried looking in the nVidia control panel to see if I could see the two cards but I could only find the one (Palit nVidia GT 9500 1gb HDMI). I continued to check in the device manager and again only the one card showed. However my friend was adament that he had paid for an SLi configured dual GPU system, so I checked the back and sure enough it has two seperate GPU outputs and checking inside it had two seperate cards.

I always assumed that in order for a card to operate in SLi that it needed some form of bridge connecting the two cards but this doesn't have that. In addition to this neither card has any power cables running to it (which I found weird, although one card was showing up so it was obviously working). Lastly when trying to connect using the cards the top card never works with VGA or DVI and the bottom card works fine with both VGA and DVI.

So what am I doing wrong in order to get these two cards running successfully in SLi so my friend can get his computer running to its potential as right now it feels as though hes got a second GPU sat in his tower for nothing.

Thanks
S

[watercooled]

What motherboard is it? Even if it has two PCI-E 16x slots doesn't mean it will do SLI. Also are there power sockets on the cards? Are there SLI contacts on the top of the cards for a bridge? The second card may not be working if he's using Vista because it disables any cards without a monitor connected to save power (unless you're using SLI of course).

[Sacred]

What motherboard is it? Even if it has two PCI-E 16x slots doesn't mean it will do SLI. Also are there power sockets on the cards? Are there SLI contacts on the top of the cards for a bridge? The second card may not be working if he's using Vista because it disables any cards without a monitor connected to save power (unless you're using SLI of course).

I've ran everest and it doesn't say what MOBO it is :s

However the board does have SLi printed on it and a small black "chip" with a sticker on that also mentions SLi. Hes running Win7 64bit but I con't see any bridge connections on the cards only a connection for HD audio (??). Also even if the top graphics card has a monitor plugged in from startup it still doesn't work.

Thanks,
S

[matty-hodgson]

Is that your card?
According to NVIDIA it doesn't require external power but it does support SLI.

You just need one of them SLI bridges and it'll be fine

[Sacred]

Thats the card thats in his system, just looking at it I can't see any ability to bridge the cards together as it doesn't have anything along any of the sides to use to connect them together.

The only thing I can think is that the card doesnt support SLi and in which case he was miss-sold his computer with promises of both cards in SLi.

[watercooled]

This one? http://www.palit.biz/main/vgapro.php?id=733 It does mention SLI on the specs but it doesn't look like it has a bridge header. But saying that SLI doesn't necessarily need a bridge AFAIK but it will probably affect performance. Is the card listed in device manager? Also has he reformatted the PC or messed about with settings? If not then it does sound like it's been mis-sold, possibly to get rid of the cards as two 9500 wouldn't have been my first choice at that price range, a single card for the same price should have been much better on most games.

[Sacred]

This one? http://www.palit.biz/main/vgapro.php?id=733 It does mention SLI on the specs but it doesn't look like it has a bridge header. But saying that SLI doesn't necessarily need a bridge AFAIK but it will probably affect performance. Is the card listed in device manager? Also has he reformatted the PC or messed about with settings? If not then it does sound like it's been mis-sold, possibly to get rid of the cards as two 9500 wouldn't have been my first choice at that price range, a single card for the same price should have been much better on most games.

Hi Water,

Yeah thats the card thats in his system. One of the cards is listed in the device manager the other isn't.
The only thing hes done AFAIK is install Windows 7 64bit everything else is the same as its always been. Having read about you're right you can have SLi without a bridge but wouldn't both cards still show up in the device manager?
I've had a look in the BIOS and it doesn't show the two cards there either, infact the only option with regards to the GPU was to choose between PCI and PCI-E (its set to PCI).

So assuming no bridge is needed then it should be able to connect the two cards using software and just the MOBO right? But in order to do that I would still have to get both cards to show in the device manager?

[watercooled]

That motherboard option is just to choose the first VGA device, if you have both a PCI and PCI-E card which one should it display on first. I'm thinking the card may either be faulty or it's not connected properly, double check it's properly seated in the slot.

[Sacred]

That motherboard option is just to choose the first VGA device, if you have both a PCI and PCI-E card which one should it display on first. I'm thinking the card may either be faulty or it's not connected properly, double check it's properly seated in the slot.

Ah right, I've took the cards out and swapped them round inside. The functioning card is still working (although not picking up the nVidia drivers) and the second card isn't doing anything still and isn't showing up in the device manager.
I assume this to mean that one of the cards is faulty and its not a problem with the MOBOs' PCI slots?

[Rob_B]

Swap the two cards around & see which one works then?

EDIT: Cracking post timings!

Can you try his other card in your rig? Can you try just one card at a time in different slots?

[Sacred]

Ok I've reinstalled the nVidia drivers and now both cards are showing in device manager and they are both showing in the nVidia control panel which is great! I assume the problem was incorrectly seated as from what I could tell when changing the cards over was that they had over tightened one causing it to lift slightly.

Anyway when in the nVidia control panel it says that I need to connect the two cards with an SLi connector but from looking at the cards this isn't possible, any ideas as to what I need to do?

[watercooled]

Maybe he was using drivers downloaded by Windows Update rather than manually installing them, they are generally not very good and/or very outdated so just doing that should have increased performance if that's the case. Can you continue without connecting a bridge?

[matty-hodgson]

Are you sure the cards are NVIDIA 9500 GTs? NVIDIA say that they should have the "SLI joiny bits" on them.

[Sacred]

Had a bit of a play about and a read on wiki and apparently as you correctly assume Water is that the MOBO acts as the bridge.

Having just ran the FFXIV benchmark hes gone from a score of 724 to 1592 without any other tweaking of his CPU or running something to close down all background programs.

[Platinum]

AFAIK with such low end cards, and yes they are very entry level not really decent gaming cards, the SLI function can be done via the PCI-E links and theres not that much info being transferred.

Disable SLI in the drivers then benchmark, enable it and bench again, if its faster all is working well

Although why the hell anyone would buy a PC with 2 SLI 9500's over say a 9600 or a 9800 is beyond me, for the price / performance there is just no logical reason.

[watercooled]

Probably marketing bull from a sales rep selling to a customer who wasn't aware..