Outside the Lines - GPU load balancing visualization

Outside the Lines - GPU load balancing visualization

Dear Mad Mod Mike,

I just bought a nice new system from Cyberpower systems with your GeForce 7800 GTX video cards. When I turn on SLI and start up a game (BF1942, BF2, Silent Hunter 3) I get a green vertical and horizontal line on my screen. The horizontal line tends to move up and down while the vertical one stays still.

I updated my drivers but this did not fix my problem.

Please help

Thank you,



Johnny! Don't tell me you pulled me away from playing with my new phase change cooling to ask me a question that is already in the FAQs! Tell me it isn't so!

Here is the FAQ:

What are the green lines that appear on my screen when in SLI Mode?
If you see horizontal or vertical green lines on your screen (shown here), it means that you have "Show GPU load balancing" enabled in the NVIDIA Display control panel. When enabled, this option shows how your GPUs are sharing the graphics load. For games that are rendered using AFR (alternate frame rendering), the vertical line will grow up and down, depending on the amount of scaling. For games that are rendered using SFR (split-frame rendering), the horizontal line will move up and down, showing how the load is being balanced between each GPU. If the upper half and the lower half of the screen have a similar level of detail, the horizontal line will stay close to the middle.
Since you already pulled me away from tinkering with refrigerant & compressors, let me expand on this a little more for you. The 2 lines you're seeing are a visual feedback feature of SLI called "Show GPU load balancing." I really only find them useful to turn on when my friends come over to show them how cool my SLI Rig is. The lines show the SLI load balancing. Obviously you wouldn't want to game with these lines turned on!

To turn SLI load balancing on and off, simply follow these steps to get to the screen you see below:
1) Right click on your desktop and select "Properties."
2) Select the "Settings" tab.
3) Select the "Advanced" button in the lower right corner.
4) Click on the "GeForce 7800 GTX" Tab in the upper right hand corner (or whatever GPU you are using).
5) On the left now appears a menu; select the "SLI Multi GPU" tab
6) Two checkboxes now appear: "Enable SLI Multi GPU" and "Show GPU load balancing"
7) If you want to show the load balancing (green lines) make sure that box is checked; if you don't, make sure it's unchecked.
8) Once you've made up your mind, click "Apply"

So there you have it - nothing's wrong with your system or your driver - you just needed to do some homework. I don't want to rub it in, since you're not the ONLY one to ask …but this common question is already answered in our FAQ section. I love helping you guys out, but please, PLEASE be sure to check out the FAQ's before asking a question - I can only read and answer so many.

This should make BF2 a little more enjoyable for you ;)

Have Fun,


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