How do I install SLI 660 Ti's with a 2 6 pin PSU?

[rhysneville]

Here's my setup
CPU - Intel i7 2600 @3.40GHz
GPU - EVGA NVIDIA GTX 660 Ti
RAM - 8GB (Speed: PC3-10600 MB/sec,Type: DDR3-1333)
Motherboard - MSI Z77A-G45
PSU - OCZ-ZS650W-UK ATX 650w PSU
HDD - 2TB (Interface: SATA, Rotational Speed: 5400 RPM)
Blu ray disk drive (not sure about specs)
Case- Zalman Z11 Plus

Can someone tell me how I'd go about setting up a 2nd 660 Ti, in as much detail as possible.. my first time dealing with SLI. 😛

I'm going to buy a SLI bridge connector for £5 ( http://www.ecrater.co.uk/p/17710326/asus-long-flexible-nvidia-video?gps=1)
but what other cables do I need?
Someone said I need to buy these : http://www.amazon.co.uk/Startech-com-Express-Power-Splitter-Cable/dp/B004NNTVT6/ref=pd_sim_computers_4
and someone else said I don't need those, he said I should just use the 4 pin power molex adapter that came with the card - http://www.playtool.com/pages/psuconnectors/pcie6.jpg

What do I REALLY need?
If you could tell me what plugs into what and a simple quick installation guide that would be awesome!

 

[Neospiral]

Firstly, you're going to need a bigger power supply to run two GPU's comfortably. I'd recommend a 750w or so high efficiency PSU. Preferably a Corsair, Seasonic, XFX, or other good brand.

Now, with the new PSU, it should have multiple PCIe connectors, so you can use those (never use adapters if you can help it). Just seat the new card right below the old one (make sure it's at least the same memory capacity and same GPU, manufacturer and clock speed don't matter) in the second PCI-e slot. Connect the SLI bridge, and in nVidia control panel under 3d/physx settings, click the radio button 'Maximize 3D performance' and you're done.

 

[rhysneville]

Firstly, you're going to need a bigger power supply to run two GPU's comfortably. I'd recommend a 750w or so high efficiency PSU. Preferably a Corsair, Seasonic, XFX, or other good brand.

Now, with the new PSU, it should have multiple PCIe connectors, so you can use those (never use adapters if you can help it). Just seat the new card right below the old one (make sure it's at least the same memory capacity and same GPU, manufacturer and clock speed don't matter) in the second PCI-e slot. Connect the SLI bridge, and in nVidia control panel under 3d/physx settings, click the radio button 'Maximize 3D performance' and you're done.

People use a 650w psu with sli 660ti's though?🙁
What would happen if my psu wasn't powerful enough, it wouldn't break the components, they just wouldn't function properly until I changed the PSU right?
Why shouldn't I use the adapters? That's what my plan was..

 

[rhysneville]

Thanks for your help though!

 

[Neospiral]

Firstly, you're going to need a bigger power supply to run two GPU's comfortably. I'd recommend a 750w or so high efficiency PSU. Preferably a Corsair, Seasonic, XFX, or other good brand.

Now, with the new PSU, it should have multiple PCIe connectors, so you can use those (never use adapters if you can help it). Just seat the new card right below the old one (make sure it's at least the same memory capacity and same GPU, manufacturer and clock speed don't matter) in the second PCI-e slot. Connect the SLI bridge, and in nVidia control panel under 3d/physx settings, click the radio button 'Maximize 3D performance' and you're done.

People use a 650w psu with sli 660ti's though?🙁
What would happen if my psu wasn't powerful enough, it wouldn't break the components, they just wouldn't function properly until I changed the PSU right?
Why shouldn't I use the adapters? That's what my plan was..

Right, if you don't have an adequate power supply, the cards won't get enough power and you likely won't be able to get a picture. Or, you can get into Windows, but running a game will cause a restart.

For the 750w, I think it's just me being conservative. You could do it with a 650w, as long as it's good quality/high efficiency. Since the OCZ isn't rated in that regard, I really couldn't tell you.

For the adapters, the risk is that the regular molex connectors aren't really designed to carry the type and amount of power the PCIe ports need. You'll lose some efficiency in the transfer, which is another reason to look at a new PSU. Honestly, it won't really hurt your components to give it a shot with what you have, but know that if you run into these types of issues, it's probably the power supply.

 

[rhysneville]

Firstly, you're going to need a bigger power supply to run two GPU's comfortably. I'd recommend a 750w or so high efficiency PSU. Preferably a Corsair, Seasonic, XFX, or other good brand.

Now, with the new PSU, it should have multiple PCIe connectors, so you can use those (never use adapters if you can help it). Just seat the new card right below the old one (make sure it's at least the same memory capacity and same GPU, manufacturer and clock speed don't matter) in the second PCI-e slot. Connect the SLI bridge, and in nVidia control panel under 3d/physx settings, click the radio button 'Maximize 3D performance' and you're done.

People use a 650w psu with sli 660ti's though?🙁
What would happen if my psu wasn't powerful enough, it wouldn't break the components, they just wouldn't function properly until I changed the PSU right?
Why shouldn't I use the adapters? That's what my plan was..

Right, if you don't have an adequate power supply, the cards won't get enough power and you likely won't be able to get a picture. Or, you can get into Windows, but running a game will cause a restart.

For the 750w, I think it's just me being conservative. You could do it with a 650w, as long as it's good quality/high efficiency. Since the OCZ isn't rated in that regard, I really couldn't tell you.

For the adapters, the risk is that the regular molex connectors aren't really designed to carry the type and amount of power the PCIe ports need. You'll lose some efficiency in the transfer, which is another reason to look at a new PSU. Honestly, it won't really hurt your components to give it a shot with what you have, but know that if you run into these types of issues, it's probably the power supply.

Ah well that's okay then, yeah man I'll give it a shot with my current PSU and see how it turns out! Thanks a lot for your help!

 

[Neospiral]

No problem. Good luck!

 

[rhysneville]

No problem. Good luck!

Thank you!

 

[rhysneville]

Firstly, you're going to need a bigger power supply to run two GPU's comfortably. I'd recommend a 750w or so high efficiency PSU. Preferably a Corsair, Seasonic, XFX, or other good brand.

Now, with the new PSU, it should have multiple PCIe connectors, so you can use those (never use adapters if you can help it). Just seat the new card right below the old one (make sure it's at least the same memory capacity and same GPU, manufacturer and clock speed don't matter) in the second PCI-e slot. Connect the SLI bridge, and in nVidia control panel under 3d/physx settings, click the radio button 'Maximize 3D performance' and you're done.

People use a 650w psu with sli 660ti's though?🙁
What would happen if my psu wasn't powerful enough, it wouldn't break the components, they just wouldn't function properly until I changed the PSU right?
Why shouldn't I use the adapters? That's what my plan was..

Right, if you don't have an adequate power supply, the cards won't get enough power and you likely won't be able to get a picture. Or, you can get into Windows, but running a game will cause a restart.

For the 750w, I think it's just me being conservative. You could do it with a 650w, as long as it's good quality/high efficiency. Since the OCZ isn't rated in that regard, I really couldn't tell you.

For the adapters, the risk is that the regular molex connectors aren't really designed to carry the type and amount of power the PCIe ports need. You'll lose some efficiency in the transfer, which is another reason to look at a new PSU. Honestly, it won't really hurt your components to give it a shot with what you have, but know that if you run into these types of issues, it's probably the power supply.

I can't choose you as the solution :/
But I ended up buying a corsair cx750 for £45, used for a month, now all i need is another 660 ti! haha