Hello, I have a problem with LR 3.5 apparently causing my aging 2.16 core 2 intel MB pro to shut down. I start up, open Lroom after a minute computer shuts down, i thought it was possibly a power cable problem at first, I was in a slight panic last night whilst this was happening and reverted back to LR 3.4 and that solved the immediate problem of computer closing down. I have fortunately never had any problems with Lroom upgrades in the past . I also noticed after upgrade that export took almost twice as long to convert a Nikon D3 nef to a full size jpeg, it was around 5-6 seconds now its pushing 13 seconds per file. This has now continued in the 3.4 version. I am wondering if my computer is gradually dying and or mixture of incompatible with upgrade. Other programs InDes, Pshop appear to work ok, Photo Mechanic runs possibly a little slower but nothing dramatic. Hard disc is 2 years old and under half full 140 gb / 320 gb. Any ideas on how to proceed, other than a trip to the Apple store which I am trying my best to put off. Thanks Adrian.