Tree flashing "icicles" graphics problem

I've been having an issue with trees on my land over the past couple of months. Well, it's my graphics issue, others don't see what I'm seeing. Some tree leaves and branches look like they have flashing icicles on them. I've played around with the graphics settings in preferences, but they make no difference. My graphics card is an ATI Radeon HD 3600 Series, and the PC processor and OS: Intel Core2 Quad Q6600 2.40 Ghz with 4 Gb of memory (32 bit OS - Windows Vista Ultimate). Any ideas how to fix this? Thanks.

Have you turned off VBO in the hardware options in the graphics tab under Preferences? That sometimes creates jagged angular shapes on ATI cards.
Another possibility is to increase the RenderTreeLODFactor value in Debug Settings under the Advanced tab (ctrl/alt/D if you haven't got Advanced menu disolayed).

Drifter: Thanks for the quick response, it's greatly appreciated.

Unfortunately, I tried those 2 settings but still get the flashing icicles on trees, even after clearing my cache and logging back in after making the changes. I set the RenderTreeLODFactor to between 2 and 3, cleared my cache and relogged, still flashing icicles, then bumped this to 5.075, cleared cache and relogged, but still no luck, both times with VBO unchecked.

Are you dealing with graphical artifacts with anything other than trees? If so, your video card could be getting too hot.

Vance: I'm not sure what you mean by "graphical artifacts". I just have a few Web browser windows open, no videos running. However, if it is a hot graphics card, would a valid test of this be for me to turn off my PC, let it cool for an hour or 2, then log back in and immediately login to SL? i.e. before I did any other heavy graphics loading? Thanks.

That would probably work. If you don't have the problem after you try that, then it's likely to be overheating.

I'm not sure what you're describing, but I've found that 'Advanced>> Rendering>> Fast Alpha' creates a bright jagged line around some alpha textures, like those used in trees. If I disable fast alpha, it goes but I get the classic alpha-sorting problem. You pays your money & takes your choice.

Kelli: that was it! I turned "Fast Alpha" off and the shining icicles on the trees disappeared immediately. What does Fast Alpha do? i.e. what's the draw back from having it turned off? I'm not aware of the "classic alpha-sorting problem", so any enlightenment would be great appreciated. Thanks!

The alpha-sorting problem is caused when you have multiple layers of alpha textures displayed. The back layer often appears in front of the closer layers. I've been told it's a function of the graphics standard SL works on, not the viewer software.

Fast alpha (somehow) goes a long way to fixing it, but not without its own issues, it seems. Glad I could help, anyway.