Windows XP 64-bit beta performance tested
AnandTech has tested
the performance of the Windows XP 64-bit public preview that was released
last week, and while it's hard to draw concrete conclusions from the performance of an unfinished OS with beta drivers and unoptimized software, it looks like Windows XP 64-bit and its drivers are far from ready for prime time. Though AnandTech's tests show performance gains with DivX 5.1.1 encoding and a 64-bit version of SiSoft Sandra 2004, gaming tests yield an average performance loss of almost 30%, and some 32-bit applications failed to install completely.
WinXP-64's horrible gaming performance can probably be blamed on flaky beta drivers, but a bigger problem may be the drivers that don't exist. According to this article over at The Inquirer, less than 50% of WinXP-64's drivers are finished, which doesn't sound encouraging at all.