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When I watch Netflix on Safari or Chrome on OS X Snow Leopard (with the latest version of Silverlight), the computer gets fairly hot.

Is this a problem with the way Silverlight is programmed for OS X? I have tried a program called gxfCardStatus which allows you to choose which GPU you use, but I'm not sure Safari even has GPU acceleration. So maybe the problem is Silverlight is working the processor too hard?

Also, when I do other things, like watching Quicktime movies, my computer runs cool.

I'd like to hear some of your ideas. My last laptop (PC) never had a problem with Netflix instant stream.

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Open /Applications/Utilities/Activity Monitor and compare CPU activity when you play the Netflix Silverlight movies, and when you play movies using QuickTime Player. Is there a considerable difference?

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Thanks for the response! I ran the test you mentioned: The Silverlight plug-in takes about 50% of the CPU (the i7 2GHz), with Safari at around 7%. A 1080p m4v movie running in Quicktime in full-screen takes around 25%. – Derek Apr 17 '11 at 12:16
@Derek There's probably your reason. Silverlight isn't as efficient, and that produces heat. – Daniel Beck Apr 17 '11 at 13:01
+1, Same issue here. Silverlight and OS X don't seem to like each other too much. – slhck Apr 17 '11 at 14:44
Are there any alternatives? Or perhaps adjustments I could make? My wife has to put a blanket between herself and the Macbook when watching a movie on the bed :P – Derek Apr 17 '11 at 15:30
@Derek Unlikely, unless Netflix offers MP4 playback using Safari's QuickTime plugin for Mac users. You could try other browsers instead, but as Silverlight needs the processing resources and not Safari, I don't think it'll help a lot. – Daniel Beck Apr 17 '11 at 15:32

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