Need assistance with SLI

[rewclaus]

I am new to SLI, so bear with me.

I had two computers that were pretty much exactly the same. I decided last weekend that the one that doesn't get used very much anymore should be stripped for parts to add to my current rig.

So I took the 8600 GT from the 2nd machine and installed it in my machine alongside another identical 8600 GT. Placed the SLI bridge on, and booted the machine up.My device manager recognizes both cards, but when I go to enable SLI in the Nvidia CP, there is no option. I have browsed around and tried many various options including re-installing drivers for both cards. Reinstalling the nForce driver. However nothing has changed in all my attempts. Surely there must be something I am missing. Any help is greatly appreciated.

My current setup is:
Windows 7 Professional 64-Bit
Nvidia nForce 680i LT SLI
Intel Core 2 Quad (Q6600)
8 GB RAM
2x GeForce 8600 GT
--Driver for both cards is ver 8.17.12.6658 (dated 1/7/2011)

[ShyguyXPC]

Does your motherboard have an SLI Selector card on the motherboard? (Usually sits between both the PCI Express Slots), if it does (not all boards did, some used this older method of enabling SLI, others did it automatically), then you need to swap the Selector card around so that SLI is enabled.

Whats the exact model of your Motherboard? Not just the chipset used.

[rewclaus]

Isn't it just Nvidia nForce 680i LT SLI? I'm not sure what else I can put down for it.

[rewclaus]

From DxDiag

Operating System: Windows 7 Professional 64-bit (6.1, Build 7600) (7600.win7_gdr.101026-1503)
Language: English (Regional Setting: English)
System Manufacturer: NVIDIA
System Model: NFORCE 680i LT SLI
BIOS: Phoenix - AwardBIOS v6.00PG
Processor: Intel(R) Core(TM)2 Quad CPU Q6600 @ 2.40GHz (4 CPUs), ~2.4GHz
Memory: 8192MB RAM
Available OS Memory: 8190MB RAM
Page File: 3309MB used, 13069MB available
Windows Dir: C:\Windows
DirectX Version: DirectX 11
DX Setup Parameters: Not found
User DPI Setting: Using System DPI
System DPI Setting: 96 DPI (100 percent)
DWM DPI Scaling: Disabled
DxDiag Version: 6.01.7600.16385 64bit Unicode

[ShyguyXPC]

Isn't it just Nvidia nForce 680i LT SLI? I'm not sure what else I can put down for it.

Like I said, thats the Chipset, not the motherboard Model.


The motherboard uses a Nvidia Nforce 680i LT SLI capable Chipset.



Look at the motherboard, see if there's a Brand/Model Screen printed on the board.



Otherwise, Download and Install this program Speccy

Run the program, let it gather the data, and then list what it states for the Motherboard Model.

For example, mine shows this:

Manufacturer MSI
Model MSI X58 PLATINUM(MS-7522)
Version 1.0

Which I already knew, but just as an example.

[rewclaus]

From Speccy:

Manufacturer NVIDIA
Model NFORCE 680i LT SLI
Version 2
Chipset Vendor NVIDIA
Chipset Model nForce 680i SLI SPP
Chipset Revision A2
Southbridge Vendor NVIDIA
Southbridge Model nForce 680i SLI MCP
Southbridge Revision A2

[ShyguyXPC]

Nah, thats not right, as far as I know Nvidia doesn't make Motherboards, never did, only the chipsets that are on the boards.

Here's the motherboard I used to have (Nvidia 650i SLI chipset): Newegg.com - MSI P6N SLI Platinum LGA 775 NVIDIA nForce 650i SLI ATX Intel Motherboard

Look at the pics for it and look at the Top down one, you'll see a small card inserted between the 1st PCI Express x16 slot and the 1st PCI Slot.

Thats the SLI Selector card, does your Board have one of these? If not, then SLI should be automatically detected on your board, and switch.




If it does have one? you'll need to take that card out, rotate it and flip it over, insert securely back into the slot it was in, and then restart your system (make sure your PC is off, and unplugged from wall before doing this. You may also (most likely) need to remove your Video cards to remove and reinsert the card.

[rewclaus]

Aha...found the little tag on the mobo. Made by XFX. Haven't had a chance to look at the picture of the msi yet.

[ShyguyXPC]

Alright, then its an XFX 680i LT SLI board.

This your board? Newegg.com - Computer Parts, PC Components, Laptop Computers, LED LCD TV, Digital Cameras and more!

Missing the middle "3rd" PCI Express x16 slot, the LT models I believe were 2 Slot only, the Standard 680i models had 3 slots.

If thats your board, you have no SLI Selector card and it should detect it automatically.

[rewclaus]

Yes, that is my board. Unforunately it does not recognise the sli, nor is there an option in the nvidia control panel. Suggestions?

[ShyguyXPC]

Take the 2nd Card out, and plug the first primary card into the 2nd Slot, boot the PC and see if it recognizes the card or not.

Also try the 2nd card in the primary slot, see if it boots from the 2nd card.

Could be a dead slot or card. Though if it worked in the other PC, it shouldn't be a dead card.

I know there were a LOT of Refurbished XFX 680i LT boards on the market over the last 2 years, I suspect it could be a slot issue, but hard to say.

Most of the Nvidia 6xx Series especially 680 series Chipset Motherboards had a lot of issues, from boot up problems to SLI issues, that were never really resolved, and fixed in the 700 series boards.


Can you check the Boards BIOS settings and see if there is any sort of SLI Setting in the Bios to enable it?

if Device manager detects both cards, and their the same, the Nvidia Display Drivers should see the 2 cards and be able to allow the SLI option in control panel.




Just out of curiousity, What power Supply are you running right now?

[ShyguyXPC]

Ooooh, Just saw something.

Near the IDE connector on your motherboard, Do you have a 4 pin Molex connector like in that picture.

If so, do you have a 4 pin from the Power supply plugged into it?


If not, try that, restart the system (shut it down first and connect the cable), see if that helps.



If you already have it plugged in, unplug it, and start system and see if that works.

Doing some google searches there was a reference on another forums where a Person was told by XFX tech support to unplug that connector with their SLI setup, that person never posted back, so no idea if it worked.

But try that see if it helps.

[rewclaus]

WEll, I did have a molex plug next to the IDE. Unplugging it did not fix the issue.
Next I tried completely, completely unistalling my graphics cards along wiht all my nvidia drivers. After rebooting, reinstalling, and reooting....nothing. So I thought "what the hell...let's dig through properties of my cards". This i swhat I have found out:

From Speccy:

GeForce 8600 GT
GPU G84
Device ID 10DE-0402
Revision A2
Subvendor XFX Pine Group (1682)
Current Performance Level Level 1
Current GPU Clock 620 MHz
Current Memory Clock 800 MHz
Current Shader Clock 1355 MHz
Current Performance Level Level 1
Current GPU Clock 540 MHz
Current Memory Clock 700 MHz
Current Shader Clock 1188 MHz
Technology 81 nm
Die Size 169 nmІ
Transistors 289 M
Release Date Apr 17, 2007
DirectX Support 10.0
DirectX Shader Model 4.0
OpenGL Support 3.0
Bus Interface PCI Express x16
Temperature 64 °C
SLI Disabled
ForceWare version 260.99
BIOS Version 60.84.18.00.1a
ROPs 8
Shaders 32 unified
Memory Type GDDR3
Memory 256 MB
Bus Width 128 Bit
Count of performance levels : 1
Level 0
GPU Clock 620 MHz
Memory Clock 800 MHz
Shader Clock 1355 MHz
Count of performance levels : 1
Level 0
GPU Clock 540 MHz
Memory Clock 700 MHz
Shader Clock 1188 MHz
GeForce 8600 GT
GPU G84
Device ID 10DE-0402
Revision A2
Subvendor XFX Pine Group (1682)
Current Performance Level Level 1
Current GPU Clock 620 MHz
Current Memory Clock 800 MHz
Current Shader Clock 1355 MHz
Current Performance Level Level 1
Current GPU Clock 540 MHz
Current Memory Clock 700 MHz
Current Shader Clock 1188 MHz
Technology 81 nm
Die Size 169 nmІ
Transistors 289 M
Release Date Apr 17, 2007
DirectX Support 10.0
DirectX Shader Model 4.0
OpenGL Support 3.0
Bus Interface PCI Express x16
Temperature 57 °C
SLI Disabled
ForceWare version 260.99
BIOS Version 60.84.58.00.12
ROPs 8
Shaders 32 unified
Memory Type GDDR3
Physical Memory 512 MB
Virtual Memory 256 MB
Bus Width 128 Bit
Count of performance levels : 1
Level 0
GPU Clock 620 MHz
Memory Clock 800 MHz
Shader Clock 1355 MHz
Count of performance levels : 1
Level 0
GPU Clock 540 MHz
Memory Clock 700 MHz
Shader Clock 1188 MHz

and from Device Manager:

GPU processor: GeForce 8600 GT
Driver version: 260.99
CUDA Cores: 32
Core clock: 620 MHz
Shader clock: 1355 MHz
Memory clock: 800 MHz (1600 MHz data rate)
Memory interface: 128-bit
Total available graphics memory: 3839 MB
Dedicated video memory: 256 MB GDDR3
System video memory: 0 MB
Shared system memory: 3583 MB
Video BIOS version: 60.84.18.00.1A
IRQ: 16
Bus: PCI Express x16
GPU processor: GeForce 8600 GT
Driver version: 260.99
CUDA Cores: 32
Core clock: 540 MHz
Shader clock: 1188 MHz
Memory clock: 700 MHz (1400 MHz data rate)
Memory interface: 128-bit
Total available graphics memory: 4095 MB
Dedicated video memory: 512 MB GDDR3
System video memory: 0 MB
Shared system memory: 3583 MB
Video BIOS version: 60.84.58.00.12
IRQ: 16
Bus: PCI Express x16

I guess the cards aren't exactly the same. Would that matter at all?

[ShyguyXPC]

It shouldn't, all thats requires is the same GPU, their Both G84 Cores, same specs (Core, Memory and Shader Clock speeds, as well as Memory Capacity, Memory Bus Width).

So thats all that should matter.


Hard to tell from that listing, is one card a 256MB and the other 512MB? Or are they both 256MB?


In any case, it shouldn't matter, if the one was 512MB, when run in SLI with a 256MB model, the 512MB one would just lose 256MB extra memory is all.



Download and Run GPUz: GPU-Z Video card GPU Information Utility

Doesn't require installation, its just an executable file.

But it will give a break of specs for each GPU (have to select each GPU in a drop down box on main tab.

On the main tab, in the section that says Memory size, see what it says for each card.




But other than that, not really sure why they aren't running in SLI.

I'm going to PM one of the other guys and see if he knows I think he used to run a Regular 680i SLI board, so he might have more insight on the issue.

Sent a message on Facebook, I know he's not on here that much these days, mainly over at Overclock.net and one other forum.

Will see if he replies soon, or in the next day or so.

[KarmaKiller]

I didn't get to read the whole thread (running out the door) but have you updated to the latest bios? Also I would wipe the drivers, run driver sweeper, then reload possibly some older drivers from the era of when those cards where popular. Lately I've been running older drivers with better performance in games and folding even on older generation cards. It's worth a shot.
And if none of that works then your getting into some more serious steps. Like flashing the bios on the cards and going from there.

EDIT:
Did you install the drivers with both cards installed, or only 1? Might try installing with 1 card, then shutting down and installing the 2nd card, then installing drivers again. I had to do that on one of the systems I had with a board similar to this.

[rewclaus]

I didn't get to read the whole thread (running out the door) but have you updated to the latest bios?

The bios of the mobo? I haven't done that yet.

Also I would wipe the drivers, run driver sweeper, then reload possibly some older drivers from the era of when those cards where popular. Lately I've been running older drivers with better performance in games and folding even on older generation cards. It's worth a shot.
And if none of that works then your getting into some more serious steps. Like flashing the bios on the cards and going from there.

I have not tried this, but will give it a shot and report back on the results.

EDIT:
Did you install the drivers with both cards installed, or only 1? Might try installing with 1 card, then shutting down and installing the 2nd card, then installing drivers again. I had to do that on one of the systems I had with a board similar to this.

I have tried uninstalling both cards. Installing one, shutting down, and installing the other. Still nothing. I did that wen I initially tried this whole SLi thing. My computer already had one card installed with up to date drivers. Put the other card in reinstalled drivers and nothing.

I am still really confused why the nvidia control panel (NCP) does not even mention SLI. I would think that even if you didn't have SLI components in your machine that the NCP would still have the space for enabling, although it would be grayed out and unusable. I don't know where else to go from here.