thanks Howl
FWIW my original post was about a specific major crash that made SL7 unusable (for me) which the beta patch solved although lots of other bug reports coming in - but this openGL issue has been around since SL6 was released.
Like you I have several PCs (and macs) and they show the same issue with SL - there is guarantee that SL will start cleanly. Just restarting SL7 corrects the problem…100% an issue with SL not with drivers/installation.
I stand by my assertion that SL7 wasn’t ready to be released and should have been held back until this first patch at the very least. If Robin thinks this is “uncivil” or “aggressive” (as he said) then I really don’t know what else to say ! I wouldn’t mind, but I’m wasting my time and effort trying to pin down the issue so it can be fixed…