Which version is for me?
Have looked at the list of downloads but am confused by a lack of choice.
I have just upgraded to an intel core2 duo (E6750).
According to # cat /proc/cpuinfo, this chip is an i686. Not sure whether it is 32 or 64bit.
The availeable choices of 64 Studio, seem to be only i386 or AMD64. Is there another choice.?

Yes!
I'll give it a go
Compatibility
32bit install for an x86-64 CPU to get VST support in ardour?
Yes thats what i mean, you
Thank you, I'll give it a go
64bit for intel
Your CPU is supposed to
Bonus, but does that mean I