Noob SLI questions

[Volatile_Mike]

Bear with me

I've got a few questions about this as I've never done SLI before. I'm thinking I might get another 680 in a few months, early next year perhaps.

I think my motherboard has got PCI-e 2.0/2.1?, would this hinder performance much in SLI as the cards are 3.0?

How much heat will 2 cards produce? Mine currently idles at 30. When gaming will easily hit 70, so the heat of 2 could be a concern.

Non reference/reference, is it best to get the exact same card I have now? or are there no gains apart from aesthetics?

Will my current CPU hold the 2 cards back from working to their full potential?

Is my current PSU good enough for an SLI setup? Its not great I dont think. I got it when I didn't know much about building a PC, and was in the " I just want to get a gaming pc working asap" mindset. It also hasn't got a 4 PCI-e power connectors, and I dont fancie using adapters, so may have just answered my own question there!

Anyway Thanks!

 

[no_1_dave]

PSU is fine
PCI-E 2.0 wont hinder performance by more then 1fps at the most
Top card will get hotter, best to keep 6xx series cards under 70c or they throttle so mount a fan blowing towards them if you can.
Reference is best for SLI as they extract the hot air
CPU will be fine for the most part, it will bottleneck some games if playing at 1080p or below. 1080p or below doesnt need SLI 680s anyway.

 

[Volatile_Mike]

Thanks for the answers, Yeah its not something I'm definitely doing. Just wanted to weigh up the pros and cons.

 

[Volatile_Mike]

*****I'm bumping this as I need advice on something,

My current 680 is 2gb, If I buy a 4gb version. Will it work out of the box no issues?? I know I can only use 2gb of 4 vram, but have read a few places that the 2 cards will not work together/have issues???

 

[ArchAndroid]

I'm pretty sure the extra VRAM will go unused. As far as I know, when using SLI or CrossFire, the same thing is loaded in the memory of both GPUs using the highest common factor, 2GB in your case.

 

[whyscotty]

*****I'm bumping this as I need advice on something,

My current 680 is 2gb, If I buy a 4gb version. Will it work out of the box no issues?? I know I can only use 2gb of 4 vram, but have read a few places that the 2 cards will not work together/have issues???

Pointless buying a 4Gb card to Sli with 2Gb Card.

There is no problem running 2 x 2Gb cards

 

[Volatile_Mike]

Pointless buying a 4Gb card to Sli with 2Gb Card.

There is no problem running 2 x 2Gb cards

Only reason I'm asking as I can get a 4GB cheaper than 2GB at the moment, thats it.

Does it work or are there problems?

 

[whyscotty]

Only reason I'm asking as I can get a 4GB cheaper than 2GB at the moment, thats it.

Does it work or are there problems?

To run cards with different vram you'll have to use a program called CoolBits(Google it)

I've never used it so can't really help you there.

 

[Volatile_Mike]

To run cards with different vram you'll have to use a program called CoolBits(Google it)

I've never used it so can't really help you there.

Thanks, you've helped me make up my mind anyway. When spending that amount of money I dont want to be fiddling with programs to get it to work. Will just stick with getting a 2gb card.

 

[whyscotty]

Thanks, you've helped me make up my mind anyway. When spending that amount of money I dont want to be fiddling with programs to get it to work. Will just stick with getting a 2gb card.

Probably a wise choice

 

[biuro74]

Two cards in SLI = +10 to temps (each). Not a rule, but "popular" observation.

Better to have OTES graphic card construction (blowing out heat outside the case, not into the case) - check GFX plastic casing.

OCZ SXS700 is not good enough for 2xGTX680, but obviously it will fire up the system with 2(2xmolex -> PEG) adaptors (6+8 PEG plugs only = possible mess with power rails).

Don't bother mobo and CPU - they are completely fine.