Hello. My Mac has never run SL particularly well, but a month ago the graphics card failed totally, creating a splurge of blurred lines whenever most apps were accessed. Apple have now changed the graphics card twice under guarantee. Now everything else on my Mac seems to run ok, but when I try to log into SL, I get a total wipe-out; the grapics go beserk, there are blurred lines and the screen flashes on and off. If I restart it all works fine. So I cannot access SL at all at the moment. I have tried the SL viewer and Firestorm with the same results. Here's the basic spec: 2011 Mac Book Pro, 10.9.5, 2.2GHz Intel Core i7 Intel HD Graphics 3000 512 MB If anyone has any ideas to offer besides 'get yourself a new laptop' which, of course, is the answer I'd choose if I had any money I'd be very grateful!