# PCI-E x1 compatible with PCI-E X16



## Elite777

I am looking to purchase a new system. The motherboard I am looking into has the following slot specs:

PCI Express 2.0 x16: 4 x PCIe x16 (@ x16, x16, x4, x4) 
PCI Express x4: 1
PCI Slots: 2

I am looking into using a PhysX card but they are listed as PCI-Express x1. Would I be able to use that card in a x4 or x 16 slot?

Also, Why do the specs list one PCI-Express x4 but lists two of them under the PCI-Express 2.0 x16?

*UPDATE*
I did a little research and read that the PhysX card won't neccassarily be needed with newer graphics cards because Nvidia will be releasing an integration of the concept through a driver/software. Does anyone know if this is valid? I heard about the integration of PhysX into Nvidia cards but not by a driver/software download.


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## HawMan

On the 8800 series the PhysX is actually done on the GPU its self, meaning a PsysX card is pointless.



As for "Also, Why do the specs list one PCI-Express x4 but lists two of them under the PCI-Express 2.0 x16?"

Im not 100% sure but im guessing its if your Running Tri SLI that the third card would be running at 4X PCI-E . ( Hense why it says 16x, 16x, 4x ).


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## Elite777

Alright, well thank you for the update on the PhysX. I am assuming the 9 Series as well as the GTX 2 Series will have the same integration. Is this a driver/software update or an actual physical component of the GPU.

Also, Say I were to pursue a QUAD-SLI configuration...Would all four cards run under x16?


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## HawMan

By Quad SLI do you mean Two 9800GX2's? If so then Yes it would be 16x / 16x.


As for the PhysX its actually built into the card and yes its on the 9 series too


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## Elite777

Alright thank you for your help. I have decided not to go with Quad-SLI for two reason though:

1) Seems to be lower in a few benchmarks unless the resolution is insanely high.
2) One GTX card is so massive (Especially the water-cooled edition one I am looking into) that it will take up two slots so if I do use Quad-SLI I won't be able to add a PCI-Express Soundcard.

Actually not that I think of it...I never really got a response on my initial question. Can I use a PCI-Express x16 on a PCI-Express slot that's a x4 or x1? I have one exta x4 slot on my motherboard so I could actually get Quad-SLI and still get the soundcard if this was possible.


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## patriothntr

What board are you looking at? It's hard to give an answer immediately...on some boards that means x4 electrical, so you need to pipe extra power in thru connectors. Others it means it is compatible, but there's a bottleneck there...

You can NOT use a VGA card in a x1 slot...they're only about an inch long...

Look at the $4000 system build that Toms hardware just did...the quad SLI didn't do so hot compared to the tri sli that they had with a former system they did. 

As far as the physx goes, I think it might be enabled on the newest 9 series cards, but it has NOT been enabled in the 8 series cards. It will supposedly be enabled at some point...I guess we shall wait and see.


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