Worse performance with sli?

[hungoverfurball]

Basically i am getting worse performance with sli gtx 580's rather then just one 580. This is happening on basically every game. As soon as i disable sli in the nvidia control panel i get the normal single card performance back but when its enabled i get half or less fps.

I have an evga gtx 580 reference design card and a zotac amp edition 580.

rest of the specs are as follows
i7-2600k 4.4
16gb 1600 ram
graphics cards are above
asus p67 ws revolution
1000w power supply (so i have enough power)

Yes i have the latest drivers installed while this is happening.

Any help would be much appreciated as this atm seems like the worst investment ever.

 

[alyoshka]

What Mobo are you using?

 

[amuffin]

Could be a crap PSU as well, but obviously which board and which DRIVERS?

 

[alyoshka]

You also need to make sure that the AMP Edition is in the Primary PCIe Slot.
If you have a mobo that allows only one card at 16x and a combination of cards at 4x.... like a few Asus Boards do, then it's better to stick to the single card solution.

 

[hungoverfurball]

You also need to make sure that the AMP Edition is in the Primary PCIe Slot.
If you have a mobo that allows only one card at 16x and a combination of cards at 4x.... like a few Asus Boards do, then it's better to stick to the single card solution.

asus p67 ws revolution and i do not have the amp in the primary slot. Is that the cause of the issue ?

 

[hungoverfurball]

Could be a crap PSU as well, but obviously which board and which DRIVERS?

asus p67 ws revolution and i actually need to update the bios for the board. Doing it now

 

[hungoverfurball]

amp edition card in my primary. latest drives same issue. Fps is 50-75% worse with sli on.

 

[amuffin]

There are four slots, have you tried different combinations? Doesn't hurt to go the trial/error route.

 

[hungoverfurball]

There are four slots, have you tried different combinations? Doesn't hurt to go the trial/error route.

yep 1 and 3 1 and 2 and all other possible been restarting all day tried different sli bridges everything

 

[hungoverfurball]

There are four slots, have you tried different combinations? Doesn't hurt to go the trial/error route.

actually just tried only my amp card and im getting the same crap performance possibly have a defective card on hands

 

[alyoshka]

Try GPUz and see if there is a difference in specs, massive difference, between the two cards. Also check the box where it shows what speed the cards are working at 4x,8x or 16x.
Post the images here if you can.

 

[hungoverfurball]

Try GPUz and see if there is a difference in specs, massive difference, between the two cards. Also check the box where it shows what speed the cards are working at 4x,8x or 16x.
Post the images here if you can.

found out the latest drivers do not work correctly with the amp edition reverted and its fine

 

[alyoshka]

Lucky you....