Re: AMD64-based laptops from HP/Compaq are crippled

From: alex goldman (hello_at_spamm.er)
Date: 07/05/05 

Date: Tue, 05 Jul 2005 00:22:20 -0700

Robert Klute wrote:

> On Mon, 04 Jul 2005 23:19:07 -0700, alex goldman <hello@spamm.er> wrote:
>
>>Robert Klute wrote:
>>
>>> On Mon, 04 Jul 2005 20:46:58 -0700, alex goldman <hello@spamm.er> wrote:
>>>
>>>>I've been researching my next laptop purchase, and whether it will run
>>>>Linux, and completely accidentally stumbled upon an alarming issue that
>>>>people need to be more aware about.
>>>>
>>>>Apparently (and if my understanding is correct), HP/Compaq disables
>>>>dual-channel memory access in Socket 939 motherboards, making CPU <->
>>>>RAM communication slower, and overall performance less than what people
>>>>would expect when buying a system with the outward characteristics of
>>>>what they think they are getting.
>>>>
>>>>http://zv6000forums.com/viewtopic.php?t=148
>>>
>>> The laptops use the Turion chip.
>>
>>Wrong. _Some_ of the laptops use the Turion chip (quite few as of this
>>writing, actually).
>
> The zv6000, the laptop under discussion here and in the forum you
> referenced, uses the Turion chip.

Wrong.

Go to hp.com,

http://www.shopping.hp.com/webapp/shopping/computer_series.do?storeName=computer_store&category=notebooks/hp_pavilion&series_name=zv6000_series&catLevel=2&tab_switch=true&tab=specs

you'll get

 Choices:
AMD Sempron(TM) 3000+ (1.8GHz/128KB L2 Cache)
AMD Sempron(TM) 3200+ (1.8GHz/256KB L2 Cache)
AMD Athlon(TM) 64 3200+ (2.0GHz/512KB L2 Cache)
AMD Athlon(TM) 64 3500+ (2.2GHz/512KB L2 Cache)
AMD Athlon(TM) 64 3800+ (2.4GHz/512KB L2 Cache)
AMD Athlon(TM) 64 4000+ (2.4GHz/1MB l2 Cache)

May I ask why you insist on spreading misinformation *after* you've been
corrected?

>>Regardless ...
>>
>>> According to AMD, the Turion's
>>> integrated memory controller can use PC1600, PC2100, PC2700 or PC3200
>>> unbuffered DDR SO-DIMMs and has a maximum throughput of 3.2 GB/s.
>>
>>Do you understand how dual-channel access works? You have 3.2 GB/s per
>>memory module, i.e. up to 6.4 GB/s. Dual-channel access is more, not less,
>>important when slow memory is used.
>
> NO, the Turion's memory controller is 64-bit and limited to a max of
> 3.2GB/s. Dual channel won't help.

Wrong. Turion is a Socket 754 CPU, so it doesn't even support dual-channel
memory access. The discussion is about the CPUs that do.

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