Re: MSI K8N Neo2 For Dual Core?

On Tue, 2005-08-23 at 18:58 -0700, Bill Broadley wrote:
> Correct, the dimms are directly attached to the CPU, but of course
> PC1600 will result in a system with a slower memory bus than PC3200.
> Thus if you have PC1600 you will get a smaller increase in performance
> with a X2 processor than you would if you had PC3200

Correct, but no different than a single CPU.
Of course, from an I/O perspective, it doesn't matter.
In fact, you'd be better off with 2x single core CPUs for I/O.

> since more often (statistically) you will be bottlenecked by the PC1600
> memory and thus deriving no benefit from your second CPU.

Huh?  How does memory affect dual-core versus single-core performance?
Single core and dual-cores still have 2 DDR channels.
A dual-core does not allow better usage of the DDR channels.

A cache miss is a cache miss, and a serious performance hit
_regardless_.  Anytime you have to write to memory, that's bad.  Anytime
you have to read from memory, that's the _death_ of performance.

BTW, do you even know how synchronous DRAM works?
[ HINT:  read latency on DRAM, even SDRAM, results in 14-40MHz
performance, because DRAM is still 25-70ns on a read. ]

> Personally I'm not ready to buy an X2 for home yet, I have PC3200 memory
> and a AMD64 3200, it's plenty fast for what I use it for and $380 for
> a x2 3800 (or more for faster) is a fair amount of cash for something
> that won't run a single thread any faster than my current machine.

Do you even have any Opteron systems?

> Not that I don't sometimes have a 2nd thread running, it's just not at
> the $380 pain threshold yet.
> So at some point it's better to hold off and hit whatever knee in the
> price/performance curve you want with a new CPU+Motherboard and maybe
> RAM combination.

Again, do you even have any Opteron systems?

> Rumors claim DDR2 for AMD64 in 2006,

It's not a rumor, AMD is gearing up for DDR2.

> I try to wait till what I can afford doubles end user performance,
> so far:
>   286     6 Mhz
> 386sx    16 Mhz
> 386dx    40 Mhz
> P5      133 Mhz
> P6      200 Mhz
> celeron 450 Mhz
> Athlon 1200 Mhz
> Amd64  2000 Mhz

Again, do you even have any Opteron systems?

> I suspect it's going to be awhile before I can find a machine
> twice as fast as my current for a reasonable (to me) amount of
> money.

Again, do you even have any Opteron systems?


-- 
Bryan J. Smith     [email protected]     http://thebs413.blogspot.com
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The best things in life are NOT free - which is why life is easiest if
you save all the bills until you can share them with the perfect woman