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

From: General Schvantzkoph (schvantzkoph_at_yahoo.com)
Date: 07/05/05 

Date: Tue, 05 Jul 2005 14:55:16 -0400

On Tue, 05 Jul 2005 11:37:29 -0700, alex goldman wrote:

> General Schvantzkoph wrote:
>
>> On Mon, 04 Jul 2005 20:46:58 -0700, alex goldman 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
>>
>> Turion's are in 754 packages not 939,
>
> What do Turions have to do with it?

You're right it's a 939, someone else mentioned the Turion which would
make sense for a notebook so I assumed that's what this one had. Where did
you get the idea that it only uses one of it's memory controllers? I don't
see any mention of that on HP's website, did I miss something?. As long as
you get two identical DIMMs it should run dual channel.

> For some tasks. For others, dual-channel will run twice faster.

I can't think of any task that you would run on a notebook where the dual
channels will make a difference. I can give you an example of the type of
task where cache size matters,

http://www.polybus.com/linux_hardware/index.htm