Monitor going off a few seconds into Secondlife

I have a nVidia GeForce 5700 FX, and as soon as i log into secondlife, my monitor flicks off. I've been playing secondlife perfectly for the past year, but since the last two updates, i've had a problem where my graphics card has become so hot it's just flicked off, requiring up to an hour's cooling time, and now the card overheats a bit, and the monitor turns off (but secondlife is working and everything is functioning), if i ctrl-q secondlife and then turn my monitor on/off i get the picture back, but i can't get it back whilst secondlife is running, so evidently the problem is in secondlife. Would appreciate help.

Well, let's resolve the hardware problem by looking at the hardware. Other than being an intensive 3D application, Second Life probably isn't the culprit; you could likely persuade Doom3 to create the same effect. Second Life can't make your graphics card turn off your monitor, but it can work your graphics card hard enough that a hardware problem manifests itself.

The two major considerations are power and heat. What's the wattage (and brand) of your power supply? Are there any cards next to the graphics card? Is there plenty of airflow in your case? Does leaving the side panel open help the issue?

Out of curiousity, does the monitor still turn off when you run SL in a window?