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I would like to add an additional graphics card in to my 2nd PCI-E slot to give me two further VGA/DVI ports along side the two on my primary card. I am unsure if this secondary PCI-E slot is for SLI only or would work with another card running together.

My main card will be faster than the secondary so I would like games to still run off the primary card.

Any advice would be great before I waste my money.

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What kind of motherboard is in your system? – cmorse May 13 '13 at 12:49
up vote 2 down vote accepted

I am unsure if this secondary PCI-E slot is for SLI only or would work with another card running together.

This is one part where you do not have to worry. There are not PCI-e connectors 'just for SLI'.


PCI-e is not even designed just foir graphical cards. Like it predecessors PCI and PCI-X it is meant for generic cards. That can be a graphical card, but also a RAID card, a serial port, a modem, a wireless card, a regular NIC, or just about anything else.

The only problem you might run into is drivers. Some older operating systems (e.g. windows XP) only support one graphical driver. If you have modern OS then this should not be a problem (e.g. Vista or newer, any or the Linux distributions, BSD's, OS X, ...)

Before you buy a new card I would:

  1. make sure that there are up to date drivers which work fine with other cards.
  2. Check if it needs 6-pin or 8-pin power plugs and if you have a PSU which can deliver that power.

PS: Please add the OS. You mentioned gaming so I assumed windows. But that is a guess on my part. And increasingly weak guess now that gaming on OS X and on Linux is gaining.

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Thanks Hennes, going to buy a very basic card so power should be fine. Running win 7 pro so drivers should be fine, got latest nvidia drivers for my current card and my new card will be nvidia as well so hopefully wont be an issue there. – user223989 May 14 '13 at 16:35
Nvidia + Nvidia should be fine, as would be Nvidia + AMD with most drivers. (A few had problems). I assume the same is true for other brands such as Matrox or Intel, but I never heard anything about those (neither anything positive nor anything negative). – Hennes May 14 '13 at 16:38

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