The latest Intel generation is called Broadwell. A 1.5ghz Broadwell would be about the speed of a 2.5ghz from 5 years ago (Sandy Bridge or Ivy Bridge).
In a large PC case, you will have to pick a 15W-17W CPU to do fanless. Fanless will be very hard for a 35W CPU.
In a small form factor, fanless would require something from the even lower-powered families. For example, the following is a 10W 2.4ghz quadcore Baytrail Atom designed for MINI-ITX cases and does not normally need a fan:
http://www.newegg.com/Product/Product.a...6813135392
There's been successful reports of Pianoteq running on 2ghz Baytrails before (and unsuccessful attempts on 1.4ghz Baytrails) so the above will be fast enough.
Looking up the Pianoteq benchmarks I ran in off-line mode on my Baytrail server, a quad-core 2.4ghz Baytrail is roughly the speed of a dual-core 1.5ghz Broadwell. The difference is you can get a full system running at 5W-10W on a Baytrail versus 15W-20W on a Broadwell. Intel sells 6W Broadwells but they are capped at 600MHz so I'd pick a 6W 1.8GHz Baytrail over that anyday.
Last edited by Mossy (04-07-2015 09:52)