My last macbook pro was one of the first gen intel macs. It had a core duo processor, not even a core 2 duo. I used to use it with an external monitor, but eventually it started to make it lag like crazy and I believe it toasted the GPU. Now I'd like to use an external monitor again with my 17" arrandale MBP, but I'm worried that an extra monitor would just slow my machine down to a halt again. I mean, I can barely use Firefox with 50 tabs open without it slowing down.