[ltp] What to take care of when buying a Lenovo?

[Christoph Lechleitner]

Michael Gaber schrieb:

>> Any T60 or later should run 64-bit Linux. I believe even the Core Solo
>> that an early T60 has should run it, but IIRC it's only clocked at
>> 1.6GHz.
>>
>> Drivers are coming along for 64-bit Linux, but I haven't tried it yet.
>>
>> Keep in mind the T60 will "only" use 3GB of RAM even with a 64-bit OS,
>> but a T61 can use 4GB but only with a 64-bit OS.

> why is that?
> i think with pae a recent system should be able to use all 4G or even more

With kernel options PAE and HIGHMEM_4GB enabled, 3 to 4 GB can be used,
dependend from BIOS and chipset capabilities. (Lenovo needed almost a
full year longer than Dell to get the BIOS right on the very same
chipset ...)

With kernel options PAE and HIGHMEM_64GB enabled, up to 64GB can be used.

Of course, some distributions don't necessarily activate those options
in their 32bit kernel, e.g. Ubuntu does not activate HIGHMEM_64GB in
their -generic kernels. (This might however change, there are some
discussions on that matter in Debian and Ubuntu kernel teams)

With 64bit kernels (distros) the CPU's phyisical address lines (usually
36 to 40) are the limit; but don't expect major multimedia codecs or
even 3rd party software to run on 64bit distros ;-((

But, ...

> The T60 doesn't use PAE. Its chipset is limited to 3GB of program
space and 1GB for I/O, at least according to Intel and Lenovo.

... is bullshit from IBM/Lenovo and proofes they don't know what they
are selling not to mention doing.

I definitively can use all the 4 Gig (of my T61p from ~July 2007) with a
32bit kernel with the correct options.

Regards Christoph