[ltp] Re: Only 3 out of 4 GB detected

Tim Prince linux-thinkpad@linux-thinkpad.org
Fri, 30 May 2008 09:33:45 -0700


Cherife Li wrote:
> On 05/30/08 19:52, Marcus Better wrote:
>> Cherife Li wrote:
>>> For my experience, I have to enable 64GB RAM support in 
>>> ernel(v2.6.25.4)
>>> to get full 4GB RAM.
>>
>> I don't see any such option in the kernel.
> CONFIG_HIGHMEM64g=y
>
> > Are you running a 64-bit kernel?
> Off course not. The CPU is just 32-bit.
> I don't know whether it is necessary to run 64-bits on Thinkpads.
>
For sure, 64-bit OS is necessary to use 4GB effectively.  If you ever 
said you were running a CPU prior to Core 2 Duo, it's no longer visible 
in the thread. 
There have been plenty of ltp posts about the pros and cons of 32- vs 
64-bit linux, and plenty of posts where people try to ignore the 
differences, making it difficult to get on the same page.  The recent 
posts indicate that I'm lucky to have a T61, where I could get benefit 
by adding RAM, although I'm happy with 2GB and SuSE 10.3 x86-64.