By Michael Lasky
Even though 64-bit PCs have been available for seven years, the promise of 64-bit computing has been delayed by a dearth of 64-bit software.
The situation is improving — slowly — but many major PC applications remain 32-bit affairs.
Microsoft likes to boast about the extra performance delivered by the 64-bit versions of Windows. Likewise, PC vendors continue to pitch the benefits of 64-bit PCs over their 32-bit brethren.
That’s all well and good — and theoretically true — but without software optimized for 64-bit machines, using those more-advanced processors for everyday tasks is like running a Formula One race car on regular gas.
The primary difference between 32-bit applications and their 64-bit counterparts is the size of memory the programs can address. Computers use only two digits (ones and zeros), so a 32-bit program can track 2^32 (2 to the 32nd power) memory addresses — about 4GB. This is the basis of the “4GB memory limit” for 32-bit hardware and software.