SLI in vista?

[IBuyUFO]

I have 2 6600GT cards. One of the 6600GT has 256 megs of ram and the other has 128 megs of ram and I'm running windows vista. The problem that I have is that when I open the nvidia control panel there is no way to enable sli. Am I missing something or does SLI still not work in vista?

 

[aka1nas]

Were you able to SLI them in XP? I thought you still couldn't SLI cards with differing amounts of RAM. I'm not sure that anything older than G80 with SLI is currently working in Vista. Perhaps someone with a setup that old can chime in.

 

[IBuyUFO]

I'm not sure if this setup would work in xp because I just recently bought another 6600gt and I already had vista installed using 1 6600gt. I would rather not go back to xp if I can help it but I'm hoping someone out there has the answer to my question.

 

[imported_redlotus]

Make sure that you upgrade to the latest drivers, currently 158.24. Most of the older drivers did not support SLI for the 6xxx and 7xxx series.

-red

*edit* forgot to mention that you shouldn't have a problem using two different memory sizes. However, both cards will be limited to using 128mb.

 

[LightningRider]

I'm pretty sure for SLI to work you need EXACT cards. So since you have separate memory amounts on each they obviously aren't the same. Therefore I don't think you will be able to run these in SLI.

Next time if you want to run SLI make sure you buy two of the exact same card to be safe. I believe the real requirement is that they run the exact same BIOS. Not entirely sure about that part though.

You are better off just buying a new card anyway, the 6600GT is an outdated card and adding another one doesn't help. SLI is only worth the money if you buy two powerful cards from the start (and only if you have a ton of $ to blow).

EDIT: Never miind, apparently you can have different BIOS versions and Memory amounts. So I am not really sure why it would not work. Except like the above user said, make sure you have the latest drivers.

 

[Woofmeister]

Let's go through your SLI checklist:

Depending on your Motherboard you may need to:

(1) Enable SLI in BIOS
(2) Enable SLI on the board either via switch or via flipable PCI board

Regardless of Motherboard, you will need to:

(1) Connect the SLI bridge to both graphics cards
(2) Plug in a power cable to the auxiliary SLI socket on the Motherboard
(3) Ensure that all power connections are made to both graphics cards

Assuming you've done all of the above and you're running Forceware 158.14 or better, you should be good on the next reboot.

Edit--I think I see your problem. Judging by your posts, it seems that you have not reinstalled Forceware following the installation of your second 6600GT. If you fail to do that, there is a significant chance that the second card will not even be detected, let alone enabled for SLI. Even if the second card shows up in hardware manager, reinstall your Forceware drivers.

 

[IBuyUFO]

This is what I've done so far.

I've flipped the mini board to SLI instead of 16+1.
Inserted the 2nd 6600 gt into the computer
forgot to say that I added the bridge for the 2 cards
reinstalled the latest forceware drivers 158.24 from nvidia's web site
vista can see 2 6600gt and gives me the option to run 4 monitors

As far as I know there is no bios option to enable or disable SLI with the exception of quad SLI which does not apply in my case.

When I go to the nvidia's control panel it has no option for SLI.
it'll suck if I go back to xp and give up all the nice eye candy that vista has

 

[Woofmeister]

Did you also plug a power cord into the auxiliary SLI socket on the Motherboard?

What motherboard do you have?

 

[IBuyUFO]

I have the epox EP-9NPA+SLI. I think I pretty much plugged all the power connectors to the motherboard. I'll double check when I get home but I'm pretty sure of it.

 

[Woofmeister]

It may not have the auxiliary power connector. When you get home, reinsert the miniboard and make sure its oriented toward SLI and make sure the SLI bridge is inserted correctly.

Other than that, I'm out of ideas.

That's a pretty old board, I wonder when the last BIOS update was?

 

[IBuyUFO]

last bios update was in 2006. Yesterday I made sure that the bridge was inserted correctly. I guess I might try to install windows xp on another drive and see if the sli feature works with it.

 

[niggles]

just went throught this myself for the first time. I'll just say what I did

1. I had to change a small cardon my asus motherboard. it said it was a patented design, but I'm guessing all mobos have something similar. I would think that there would be some kind of hardware change required beyond simply plugging the cards power in.

2. change the bios settings

3. does enabling SLI now appear in Nvidia control panel under "set SLI configuration.

That's all I remember doing.

 

[IBuyUFO]

I installed windows xp and it's still a no go. SLI does not show up. Maybe lightningrider is onto something that the cards have to be identical. This sucks. I thought it would be an easy thing to do.

 

[imported_redlotus]

Just out of curiosity, where are you looking for the SLI setting? In the latest drivers, it's not even called SLI anymore.

Doing this from memory, so please bare with me. When you open the nVidia control panel, there is a list of categories along the left hand side. Under the first main group, the third sub-category should be multiprocessor or multi display setup (or something like that). When you click on this, you should have two options:
Multi Display
Multi GPU (Recommended)

Choose the Multi GPU and click Apply. Once you reboot, you should be in SLI mode.

Hopefully I have the explanation close enough, but if anyone can fill in the exact descriptions, please do. Otherwise, I will try to remember to edit this post when I get back home this evening.

-red

 

[quattro1]

Originally posted by: redlotus
Just out of curiosity, where are you looking for the SLI setting? In the latest drivers, it's not even called SLI anymore.

Doing this from memory, so please bare with me. When you open the nVidia control panel, there is a list of categories along the left hand side. Under the first main group, the third sub-category should be multiprocessor or multi display setup (or something like that). When you click on this, you should have two options:
Multi Display
Multi GPU (Recommended)

-red

False info here, it is still called SLI. You are thinking of what the 7950GX2 displays in the conrol panel which is multi display or multi gpu(since is single card). If you have a correct setup for SLI, the SLI option will be there and is called SLI.

Believe the problem with the original poster is that he does not have the same 6600GT's. One has 256MB, the other 128MB which is breaking the option to turn on SLI.

 

[imported_redlotus]

Originally posted by: quattro1
False info here, it is still called SLI. You are thinking of what the 7950GX2 displays in the conrol panel which is multi display or multi gpu(since is single card). If you have a correct setup for SLI, the SLI option will be there and is called SLI.

Oops. Didn't realize that there was a difference (thought that the GX2 was treated just like SLI). Thanks for correcting me, though.

-red

**Edit** I think that I've found your answer. This is from slizone

Can I mix and match graphics cards with different sizes of memory?
While it is not recommended, NVIDIA does offer this flexibility using Coolbits. When purchasing a second graphics card, you should try to match the memory size so that you are ensured full value and performance from your purchase. For example, if your first card is a GeForce 6600 GT with 128MB of memory, you should purchase a second GeForce 6600 GT with 128MB of memory. However, using Coolbits (value set to 18), you can force both of the cards to use the lower of the two memory sizes and operate together in SLI mode. When dissimilar memory sizes are enabled to work together using Coolbits, the effective memory size for each card becomes the smaller of the two memory sizes. Instructions to enable this feature can be found here.

I'm not sure if coolbits is compatible with the newest drivers and/or Vista, but it's someplace to get you started.

 

[Woofmeister]

Coolbits is not compatible with the latest Nvidia drivers, which means it's not compatible with any Nvidia Vista drivers.

I think the OP is screwed.

 

[IBuyUFO]

this sucks! I want to thank you guys for trying to help me solve my problem. It's too bad it's not working out like I had hope. I'm going to try it anyway in vista to see what happens if I include the coolbits in the registry.