[CentOS] How to select a motherboard -- CPU architectures and chipsets

Thu Dec 15 16:57:11 UTC 2005
Feizhou <feizhou at graffiti.net>

> That's where HyperTransport comes in -- it offers two
> schedulers in the hope that two virtualized cores can put
> more stages to use.  It only works on the horribly
> inefficient Netburst architctures -- you will _never_ see
> HyperTransport on the Pentium-M or Intel's newer processors. 
> The concept of multi-threading on a single core lives and
> dies with NetBurst.

I think you meant HyperThreading.
> 
> The next evolution is multi-threading across multi-core.
> 
>>Yes, these are the chums in use in the newer boxes I used
>>to admin. I loved the 3ware + riser card fiasco though.
> 
> 
> Well, when you're pushing 200+ traces at 66MHz, there tends
> to be EMF/EMI issues.  3Ware isn't the only one that has had
> issues with traces.  Remember, 3Ware 7000/8000/9000S (not
> 9550SX) use 0 wait state, 64-bit ASIC+SRAM devices.  Trace
> length and timing is everything, and heavily affected by
> EMF/EMI.
> 
> Again, I refer back to the i865 v. i875 issues.  The traces
> of a PCB designed for the i875 -- such as the Asus P4C800 --
> didn't necessarly work for the exact same chip in the i865,
> because it tested to lower tolerances.

Ok, thank you for your explanation. I guess that is why we had to get 
one particular rise from one particular manufacturer.

> 
> 
>>The problems I have are related to their hardware, not
>>whether there are good drivers or not.
> 
> 
> Actually, the firmware has always been the issue.  The
> ASIC+SRAM design was always sound.  They've done some stupid
> things, like the RAID-5 firmware update for the 6000 series
> (which was _never_ designed for RAID-5).  But other than
> that, it's always been a 


I am sorry Bryan but we seem to have some misunderstanding.

3ware is on Intel 7500 motherboards.

The VIA issue is something else entirely.

> 
> 
>>The poor latencies just won't let me use a Pinnacle 
>>DC10 board without crashing.
> 
> 
> ???  Let me guess, RAID-5 on a 9500S?  ;->

This is on a KT400 VIA chipset. Nothing to do with 3ware. This is purely 
a dumb VIA chipset problem.

> The Tyan "Tiger" series is _not_ a workstation/server
> platform, it's the _desktop_ platform.  That's a very common
> misnomer.  The "Thunder" is the workstation/server series. 
> ;->

Tell that to the one who picked the board.

> 
>>I cannot wait for a promise by a Nvidia rep about their
>>future chipsets using SATA NCP technology that will allow
>>an open source driver to be written to be acted on.
> 
> 
> Do you mean NCQ?

Yes :)
> 
> Understand that nVidia is _totally_open_ with their designs
> right now, including the SATA.  But the SATA hardware just
> doesn't do NCQ at all.

Nforce4 Ultra and above support command queueing according to them.

> 
> But yes, nVidia has been extremely open.
> 
> 

Yes...where possible. Their SATA/NCQ implementation apparently does not 
allow them to provide specs or something.