2 SLI + PhysX question

[jenkas]

One question

If I have one board with 3 PCI-E, the first at 16x the second at 8x and the third at 4x, can I put two GTX 460 in sli at 8x/8x and the third PCI-E won't loose any lanes for a third card for physx like a 9600gt? or the SLI configuration will losse any lanes from the PCI-E 4x?

Sorry If i don't explain very well but I speak spanish and this is my best english lol

 

[Toxxyc]

The setup will work fine, and the 4x PCI-E will work fine with the 9800GT. The card isn't fast enough to really notice a difference in 4x, 8x or 16x.

Putting two cards in SLI in different speed slots (16x and 8x) would mean (I'd guess), both cards running at 8x. Note that it isn't a slow speed for the GTX460, as it already has the SLI bridge to increase speed, and you won't notice much difference between the two cards in SLI running at 16x than at 8x.

 

[acer0169]

So far I don't think their are any cards that really make a difference between x16x16 and x8x8. When upgrading my motherboard several months ago I thought I could see a little FPS increase (going from x8x8 to x16x16) but I think that was just wishful thinking. (GTX 260 btw).

And as Toxxyc says, the 9800GT wont make any difference in a x4 slot.

 

[jenkas]

The setup will work fine, and the 4x PCI-E will work fine with the 9800GT. The card isn't fast enough to really notice a difference in 4x, 8x or 16x.

Putting two cards in SLI in different speed slots (16x and 8x) would mean (I'd guess), both cards running at 8x. Note that it isn't a slow speed for the GTX460, as it already has the SLI bridge to increase speed, and you won't notice much difference between the two cards in SLI running at 16x than at 8x.

This is the board I want to buy

http://www.newegg.com/Product/Product.aspx?Item=N82E16813157217&cm_re=asrock_extreme4-_-13-157-217-_-Product

I will have the money by april but i want to make my homework first, I know asrock is not very popular but is cheap and in paper are great i gonna make my bet for it, my only concern was that if i could do SLI and dedicated physX, but instead the 9800gt the 9600gt will work fine too or is not enough for physX?

One last question, my PSU is a coolermaster real power 750W, I need to upgrade for the SLI+PhysX?

 

[jenkas]

Best answer selected by jenkas.

 

[bullmoosetom]

This is the board I want to buy

http://www.asrock.de/mb/photo/P67 Extreme4(m).jpg

http://www.newegg.com/Product/Product.aspx?Item=N82E16813157217&cm_re=asrock_extreme4-_-13-157-217-_-Product

I will have the money by april but i want to make my homework first, I know asrock is not very popular but is cheap and in paper are great i gonna make my bet for it, my only concern was that if i could do SLI and dedicated physX, but instead the 9800gt the 9600gt will work fine too or is not enough for physX?

One last question, my PSU is a coolermaster real power 750W, I need to upgrade for the SLI+PhysX?

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Shuld be no problem as far as I know ..except !... If you put one card in the first pcie and one in the second...that is great and good seperation between GPU 1 and 2... Problem is..that third slot is too close the the second...
Your 2nd slot card (as mine is) is so close to the third, you can hardly get a DVD disk between them... The 2nd card may starve for cool air on long running, hot games like Metro.
On another note...
I use two superclocked EVGA 460's in SLI and and a 450 for PHYSX only and my score went way up...almost double over just SLI when running the tough METRO benchmark. With PHYSX on the third card I get about the same score as if I had turned the PHYSX off when only using the SLI.
Bullmoose

 

[jenkas]

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Shuld be no problem as far as I know ..except !... If you put one card in the first pcie and one in the second...that is great and good seperation between GPU 1 and 2... Problem is..that third slot is too close the the second...
Your 2nd slot card (as mine is) is so close to the third, you can hardly get a DVD disk between them... The 2nd card may starve for cool air on long running, hot games like Metro.
On another note...
I use two superclocked EVGA 460's in SLI and and a 450 for PHYSX only and my score went way up...almost double over just SLI when running the tough METRO benchmark. With PHYSX on the third card I get about the same score as if I had turned the PHYSX off when only using the SLI.
Bullmoose

thanks for the info, but you think if i have two gtx 460 msi cyclone will overheat to? this card seems to have a more free space

 

[bullmoosetom]

Nope ! 460's in the 1st and 2nd slot will work fine as there will be about 1 and 1/16" space between the 1st and 2nd card.
It is any third card on the motherboard you pictured that will give trouble to the 2nd card by starving it of air, and any air it does get will be hot coming off the top side of the number three card, which is almost touching it.
But these 460's (even overclocked) are relatively cool and most of the heat goes out the back of the computer. So...if you are gonna run a third card, make it a cool one, because the power supply fan can also rob it of air...in my case the psu has a 140 mm fan just 1 and 1/4" below the third fan.
But all that said...I love my overclocked 460's as they give me a windows experience rate in graphics and gaming graphics of 7.8 and 7.9 depending on how fast I am running my i7 2600k. Even under stress, these two 460" are under 71 degrees in my Antec 1200.
And a vantage score of over 30 thousand 3dmarks, graphics score of over 26k...that is with a cpu score of 58k or better. Jane Nash is over 79 average fps and new calico over 75 fps.. Not too bad for cheap cards <g>
But then...Vantage says they will not publish my scores because I am cheating by running physics on my cards instead of the CPU <g>... I say "sour apples"... when a card company builds a better mouse trap...good for them... and just because other companies cant or will not do it..Why punish the better company, just because you are in bed with the compitition?
bullomoosetom