Can 32-bit Linux be installed on 64-bit laptop (and is it a good idea)?

[Jonathan Berry]

On 8/18/05, Reshat Sabiq <sabiq at csociety.org> wrote:
> >From what I remember 64-bit processors still support 32-bit exes, which
> means I should be able to run all the 32-bit software, and for that

Yes, the AMD64 processors can run 32-bit software.  You can do this in
a couple of ways.  You can run a 32-bit OS with everything 32-bit, or
you can also run a 64-bit OS and run 32-bit programs as well.  There
are a few limitations when running on 64-bit OS such as all kernel
modules must be 64-bit, you mostly cannot mix 32-bit plugins with
64-bit applications, etc.

> software the memory usage will not double. I.e., 256MB RAM for 64-bit box
> running mostly 32-bit software is not like 128MB RAM for 32-bit box. I
> suspect if the OS was 64-bit, then the OS pieces might be consuming twice
> as much memory as on 32-bit box, but I think that XP it is shipped with
> is 32-bit, which means it's not gonna be consuming twice the memory.

Whoa, I think you have a mistaken concept of 64-bit.  I'm not sure I
completely understand what you are trying to say, but a 64-bit
application does not take up twice the memory of a 32-bit application.
 It is true that a 64-bit executable can be larger than its 32-bit
counterpart, but it should be no where near twice as big.  Yes, XP
shipped with it is the 32-bit version.

> I'm
> not sure if I would have to install 64-bit Linux, instead 32-bit though.

You can install either.  I would recommend 64-bit because it is so much faster.

> If i have to, then memory usage might be doubled by Linux OS pieces, 
> perhaps even apps, if they are built for 64-bit, on Linux. Is that
> correct?

No, it isn't.  Memory requirements are the same for the same
application.  The executable may be slightly larger, but you should
not see adverse effects from this.  Theoretically, memory management
should be better in 64-bit, though I don't know how much benefit you
actually get in practice with small amounts (< 1 or 2 GB) of memory.

> Also, I should be able to add memory to it later, when it comes to that.
> This is for my relatives, and 256MB should be enough for now.

You should think about more memory, and get a 5400 RPM hard drive if
you can.  What you might do is get RAM seperately and replace the 256
MB stick (that way you can get PC3200 rather than PC2700).  More RAM
in laptops is better, and it is not that expensive (~$130 for 1 GB). 
A 4200 RPM hard drive, especially with that little RAM, will make the
system seem really slow.  Once things are in memory, though, it will
fly.  I have an R3000Z which is very similar.

> P.S. Link:
> http://www.shopping.hp.com/webapp/shopping/computer_series.do?series_name=ze2000z_series&catLevel=2&category=notebooks/hp_pavilion&storeName=computer_store

The only thing I don't like about the specs of that computer is the
ATI graphics.  You won't have 3D in Linux, but you should be able to
get most stuff working.  Compare prices with the Compaq version.  It's
the same thing, just a slightly different package.  HP and Compaq are
the same now :).  Get the less expensive one unless you just have to
have black over gray.

> Thanks.

Jonathan