[LAU] Box under £400

[Joshua D. Boyd]

On 05/31/2012 01:16 AM, Gabriel M. Beddingfield wrote:
>
> I have an Atom N450 netbook.  In practical terms, its limits for a 
> single task are:
>
>   * Time-stretching a clip in realtime to 50% to original
>     time span.
>
>   * A set with 4-5 monophonic synths, and 4-5 pure audio
>     tracks.
>
>   * All of the Renoise sample programs
>
>   * Most anything you can throw at Mixxx.
>
> While it has very good audio performance -- it has significantly less 
> headroom than a Core2 or i-series processor (feels like a factor of 2 
> or 4).

The Atoms specifically mentioned so far (until yours) were the D525 and 
the 330.  I'd also add the D510 to that list.  Those are dual core while 
the N450 is only single core.  Thus, they will probably get nearly 2x 
the speed of your N450.  The D525 also has a higher clock.  Clearly they 
still won't be as fast as a C2D, let alone a Core i3 or better.

Personally, I use a D510 (dual core, 1.6ghz, came out prior to the D525) 
and am pretty happy with it.

> Other non-audio tasks:
>
>   * Large compiles take 4-6x longer (e.g. kernel, Qt)
>
>   * Number crunching tasks are very slow.  It's like the
>     floating point stuff is driving drunk.
>
>   * Processor has a high performance hit for inefficient
>     memory access (compared to Core2, i-series).
>
>   * Processor doesn't benefit as much from SIMD (SSE)
>     optimizations.  E.g. you're lucky to get a 2x performance
>     boost using SIMD instructions... whereas a Core2 or i-series
>     will see at least a 2x performance boost.
>

I have not benchmarked my Atom extensively.  Large compiles certainly 
will be slower on it compared to some of my other machines.  I haven't 
looked at floating point specifically, but I will say that whenever I 
can be bothered to, I make sure to compile with SSE math.

>   * Most Atom devices have only 1GB RAM (2GB if you're lucky).
>     I've not seen an Atom device with more then 2GB.

The N450 in your netbook maxes out at 2GB.  I think most N models max 
out at 2 gigs.  That said, I'm not aware of very many desktop boards 
that use the N CPUs.  The D510 and D525 will usually take 4 gigs.  Atom 
330s sometimes take 4 gigs, but only if using the ION chipset, which 
means NVidia graphics.

> Finally, all this experience is in 32-bit mode.  I've been running in 
> 64-bit mode recently, but haven't done much audio with it.  Overall, 
> it feels about the same.

I doubt 64bit mode changes things.  My audio computer still runs 32bit 
linux though since I get the impression that most SSE code still targets 
32bits, for now.  That said, I have gotten the impression that the extra 
registers in 64bit mode can make an even bigger difference with Atom 
than it does with some other CPUs.

In the end, an Atom clearly isn't going to have the raw DSP power of a 
C2D or Core i3 (or better) machine.  The question though really should 
be, is it good enough to not hamper the user?  I and others have found 
it to be good enough.  OTOH, there are people who legitimately find they 
run out of CPU power with a monster 12 core Xeon desktop