On Wed, Jul 25, 2012 at 4:32 PM, Florian Philipp <li...@binarywings.net> wrote: > Am 25.07.2012 22:14, schrieb Volker Armin Hemmann: >> Am Mittwoch, 25. Juli 2012, 16:05:29 schrieb Philip Webb: >>> I've listed what's available at the local store, >>> which I trust to stock reliable items, tho' I wouldn't ask their advice. >>> >>> All the AMD's are 32 nm , while the Intel recommended by one commenter >>> -- Core i5-3570 4-Core Socket LGA1155, 3.4 Ghz, 6MB L3 Cache, 22 nm -- >>> is 22 nm : it costs CAD 230 & they have 3 in stock, >>> which suggests demand, but not the most popular ( 9 in stock). >>> >>> Isn't 22 nm going to be faster than 32 nm ? >> >> no >> > > Lower transistor size gives you two advantages: Lower current (-> > potentially lower power consumption and heat) and more transistors to do > something. The practical effects depend on what the chip maker does with > this.
I second this; the feature size limit of the process isn't really something a consumer should care about at _all_. Its only real impact is on what architectural options are open to the manufacturer, which in turn drives how much they can get out of a performance and feature balance. What you really care about is what the manufacturer builds, not the tools and materials they had available to them. > >>> >>> In the same price range, AMD offers Bulldozer X8 FX-8150 (125W) >>> 8-Core Socket AM3+, 3.6 GHz, 8Mb Cache, 32 nm ( CAD 220 , 2 in stock). >>> >>> How do you compare cores vs nm ? >> >> who cares? >> > > You cannot really compare this. If you can use more cores, e.g. because > you have an embarrassingly parallel application, by all means, get it. > Otherwise you should probably care more about single core performance. I'll note that emerge -e @world with parallel emerge and parallel make qualifies. So does running a browser like Chromium which gives each tab its own process. > >>> How far is cache size important ( 6 vs 8 MB )? >> >> depends on the architecture. >> > > In short, for all three questions: Look at benchmarks and look at the > TDP ratings if that is important to you. Good points. > > nm numbers don't tell you anything that can be directly translated into > performance or other qualities. They only allow educated guesses. If you > really want to delve so deep into chip design, you could as well look at > pipeline depths, cache associativity and such alike (not that you should). Not that that isn't fun. ^^ -- :wq
