On 03/08/2015 05:54, Jeff Liebermann wrote:
On Sun, 02 Aug 2015 22:44:32 +0100, Martin Brown
wrote:


If I was buying today price no
object then maybe i7-5930K but realistically i7 4790K. I have an
aversion to AMD due to self immolation but two are better than it.

Agreed. I haven't seen a bad Intel CPU in probably 15 years, while
I've lost count of the dead or erratic AMD CPU's that have I've had to
deal with. I would go with a 4th or 5th generation i7. The i7-4790k
is about $330 and burns about 45 watts, while the i7-5960x is $1,000
and burns 140 watts. That should make the decision easy.
https://en.wikipedia.org/wiki/List_of_Intel_Core_i7_microprocessors

Another thing to experiment with is limiting the number of threads the
simulation code is allowed to use. Mine generates more heat and less
speed when allowed to use more than 6 threads in heavy computation. It
goes IO bandwidth limited after that even with the faster ram

A fast agile SSD for scratch files and
most frequently used programs is very worthwhile.

In general, an SSD is 3x to 5x faster than rotating memory for
everything. I'm partial to Samsung 850 EVO and Pro.
http://www.newegg.com/Product/Product.aspx?Item=N82E16820147372
Most SSD drives have similar read speeds. However, the write speeds
is what makes the difference. There are benchmark tests all over the
internet. Don't overbuy on capacity as the prices of SSD drives are
still dropping and you can probably do better if you wait until you
need the space.

I have been with Samsung SSDs for a while but I'd still consider
Crucial. My requirements are for maximum speed on incompressible data. I
avoid the newest models for a few months. Been bitten by early
firmware/chipset issues once in the distant past.

If you are using it for scratch disk you can go even faster by making a
RAID0 array of matched SSDs and accepting doubling the risk of failure.


Most of my customer initially want the fastest speed and the latest
features. After those fail, they ask for reliability and uptime. Try
not to repeat this pattern and buy something that you know will work,
not that has the latest acronyms and buzzwords attached.

The gaming community make quite a good testbed since they want machines
that are fast, well specified and reliable enough to overclock. I get a
bit of teasing for having machines with daft names but performance has
been magnificent. PC companies I buy from have a tendency to go bust
after a while since they are usually offering too good value for money.

I don't overclock mine and I do add some silicone washers and sound
deadening foam here and there because I like my office quiet.

--
Regards,
Martin Brown