PCIe 2.0 x16/x16/x16 vs x16x8x8

sharr

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Hey all,

i have a bit of a dilemma on my hands regarding the bandwidth of the PCIe. My goal is to upgrade my system to a 3way-SLI using GTX 480s.

Everyone knows, that for a 2way-SLI, its best to insert the cards into 2 x PCIe 2.0 x16 supporting x16/x16 configuration. However, when u move up to a 3way-SLI setup u have a couple of options depending on your mobo: PCIe 2.0 x16 supporting x16/x16/x4 ; x16/x8/x8 ; (and the best of them all) x16/x16/x16 configurations

The question is: How much will the performance of the 3way-SLI GTX 480s be affected by anything less than PCIe 2.0 x16 supporting x16/x16/x16 configuration.

Im asking this because i was looking forward to upgrading my mobo to the RAMPAGE III EXTREME but then i noticed that its configuration of the PCIe 2.0 x16 is x16/x8/x8 for the 3way-SLI setup! I know that this mobo is a "technological masterpiece" due to its OCing capabilities and not only, but im more focused on the GPU performing best rather than the CPU if it would come down to a decision between the two. My other option would be the ASUS P6T6 WS Revolution witch supports "true" PCIe 2.0 x16 in a x16/x16/x16 configuration.

Im looking forward to all your opinions on the mater,

THX!


PS: I am apologising in advance to the admins and the community if this thread was better suited for the Graphics Card section of the forum.
 
I doubt you'd notice the difference, there was around 4% performance penalty between 16x and 8x the last time I checked on the HD 5870. The GTX 480 is a bit more powerful, but if I recall... nVidia cards are less bandwidth hungry... like the GTX 295 being two GTX 275s at GTX 260s speed used just a bit more bandwidth than the HD 4850 X2, but was much faster than it. Even if I'm wrong I doubt you'll see much of a performance penalty. If you really do want a full 16x board, you'd need to find the limited edition E759 EVGA X58 SLI Classified with the NF200 chip, otherwise... the ASUS P6T7 WS Supercomputer has dual NF200 for four way 16x/16x/16x/16x CFX/SLI. (It's got seven PCI-e 16x slots... lol.)
 

sharr

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hehe, ye, seven slots ...

i've recently discovered that the EVGA X58 SLI Classified (141-BL-E760-A1), as stated by several pple (EVGA wasnt able to provide this info anywhere), also has true PCIe 2.0 x16 supporting the x16/x16/x16 config. i will research the mater further and if its true, then this is the winner for me.

thx for the info (and reply) Lmeow!
 

tie23he

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Can I ask a question? (I am a noob)

Why would you need 3 way SLI GTX 480's?
Im not asking in a bad way. I am just curious.
I dont know much about hardware as of now so please enlighten me on the use of so much GPU Power.

Reason i ask is because i have been reading that 1 GTX 480 is a quote on quote "beast" and that it can handle anything alone. So this led me to ask, why would you need 3? WHat kind of work/games require so much?

Sorry this is kind of offtopic
 

sharr

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it turns out the EVGA X58 SLI Classified (141-BL-E760-A1) is NOT a TRUE 3way SLI mobo.

Does anyone know (FOR SURE) an EVGA mobo, besides the E759 EVGA X58 SLI Classified, with "TRUE" 3way 16x/16x/16x SLI config ? PLEASE, do tell!




OFFTOPIC:
@tie23he
hehe, no problem!

im gonna give u 3 reasons, u pick the one u like best :)

1. this rig is gonna last until the 3rd fermi generation (should nvidia choose to continue with it until then and not jump to another chip architecture) and thats about 2 years from now.

2. if u want to go for the nvidia 3d stereoscopic surround, u really need a LOT of "GPU power" as u put it.

3. once u "catch the enthusiast virus" its hard to cure yourself of it :p

PS: i ran Metro 2033 in Dx11 with the settings set to the highest (with only 1 GTX 480) and i was hovering at around 9 FPS, OUCH!, so im planning on "preparing my rig" for Crysis 2! :p
 

tie23he

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Thanx sharr for your response.

o and if u wanted to know, i liked the enthusiast virus one. ;)
althought i sure havent caught it yet.
Im the kind of guy that always sets the settings to very low automatically in all games.