[GTALUG] Build critique request and the story behind it.

[Lennart Sorensen]

On Sun, Nov 19, 2017 at 09:35:45AM -0500, Russell via talk wrote:
> One thing that confuses me is manufacturing reporting conventions. For instance the DDR4-4000 modules are described as a Column Access Strobe latency of 19. This CPU reports support for DDR4-2666 CAS 15. This number refers to the onboard cache, I think?

Well if running at 2666 speed, 15 clock cycles sounds close to what 19
clock cycles at 4000 speed would be (given how much shorter those clock
cycles would be).

4000/19 = 210
2666/15 = 177

Not quite the same, but similar.  Maybe the default values are just
conservative or that 4000 ram is very very agresive in its timings.

> I went with a single 8 gig DDR4-2666 module, just to be safe. 

Yeah super fast ram can sometimes be tricky to work with and I am not
convinced it really makes much difference.

Slower ram is usually also easier to upgrade to more ram later.
Often there are limits on the really fast stuff in terms of how many
slots are in use and matching speeds between modules.

> I wish I was better at math. I attribute some of my confusion to having been frightened off math by my having viewed  the machine math room at my vocational school. All those heavy welded tables sorting punch cards, all that noise concentrated in a small room brrrr, gave me the willies. 
> 
> I took electrical wiring (knob and tube) and mechanical drafting instead. I can calculate angles and areas using the tables of a rafter square and I'm getting better at troubleshooting DSDT acpi issues. However, I imagine those issues will be as obsolete as knob and tube wiring soon, if not already.
> 
>  support for his AMD video card has
> >been a problem.)

Yes ATI/AMD has long had a history of great hardware and crappy drivers.
I keep hoping someday they will figure out the driver issue and then
seeing that no they still haven't.

> Offhand I'm planning to put /home and /opt on the 3TB drive but if you have any recommendations for an optimal partitioning scheme for the SSD, in order to reduce writes as an effort to prolong service life, I'd appreciate it.

Well make sure to use 1MB alignment for the start of partitions.  I think
the partition tools do that by default these days anyhow.

Wear leveling ought to mean it doesn't matter how you partition though.
If you want to reduce wear, don't write to it.  Could mean writing logs
elsewhere.  Of course you do have to write quite a lot to wear out an
SSD so for most people it might not be a problem.  I certainly don't
give it any thought on my own machines.

-- 
Len Sorensen