The following information might help you decide whether to install 32-bit or 64-bit Linux on a 64-bit-capable processor.

• EM64T/AMD64 processors can run either version of Linux equally well.

• A 64-bit distribution allows each process to address more than 4 gigabytes of RAM.Larger address space is the biggest advantage of a 64-bit distribution. It is typically useful only for certain engineering/scientific computational work and when you are running multiple virtual machines.

• A 64-bit processor is not faster than a 32-bit processor in general; most benchmarks show more or less similar performance. In some cases the performance is better and in some cases it is worse: There is no clear performance advantage for either type of processor.

• The memory model for 64-bit Linux makes pointers twice as big as those in 32-bit Linux. This size difference translates to a more than 5 percent RAM usage increase, depending on the application. If a system is low on RAM, this overhead might make performance worse.

• ASLR (Address Space Layout Randomization) works better with the larger address space provided by 64-bit Linux. ALSR can help improve system security. See en.wikipedia.org/wiki/Address_space_layout_randomization.

• Some multimedia encoders run 10–30 percent faster under 64-bit Linux.

• Because more people are using 32-bit Linux, bugs in 32-bit Linux tend to be discovered and fixed faster than those in 64-bit Linux.

• Linux can set up Flashplayer and Java with a single click on 64-bit systems just as it can on 32-bit systems. However, for some applications, such as Skype, you must apply ugly workarounds to run them on 64-bit systems.

• Some features of proprietary third-party applications are not available for 64-bit architecture.

• There is no simple way to go back and forth between 32-bit and 64-bit versions of Linux without reinstalling Linux.

• If you are not sure which distribution to use, install the 32-bit version of Linux.