I help, with remote control, a few friends (15).
I and my friend: All use XP-Professional SP3. IE7.
Exactly, since the upgrade to 9.2.057, i see, on all PCs, this increases:
CPU usage : c.a. + 10/15 %
Disk C usage : c.a. + 20/20 %
RAM usage : stable
ZA Setting : SmartDefense Advisorff
Defrag off/online: good