Copied from my previous post, Memory Usage in Windows XP: https://www.wilderssecurity.com/showthread.php?t=128988 Memory usage: Ewido 18.104.22.168 Beta guard.exe 21,704K Ewido.exe 12,784K CounterSpy 1.5.82 SunThreatEngine.exe 59,336K SunProtectionServer.exe 13,532K SunServer.exe 9,624K KAV 22.214.171.1249 avp.exe 5,900K avp.exe 2,664K Ewido.exe jumped between 20-56% of the CPU time, while CounterSpy and KAV didn't have such big CPU consumption. Memory usage in my Windows 2000 (which was dual boot with Windows XP with the same hardware) Ewido 126.96.36.199 Beta guard.exe 22,204K Ewido.exe 23,236K Memory usage of Ewido.exe in Win2K nearly doubles that in Windows XP. However, half an hour later, memory usage of Ewido.exe dropped to 5,320K. Strange!!! Peak memory usage: guard.exe 67,704K Ewido.exe 68,808K NOD32 2.51.26 nod32krn.exe 17,648K nod32kui.exe 2,892K SpySweeper 188.8.131.529 spysweeper.exe 14,784K wrsssdk.exe 14,008K CPU Usage: from 1% to 88%. The fluctuation and peak is much higher than in Windows XP. Is this normal?