In Windows XP, you can check up system processes with task manager or check the memory size occupied by running software. But here you see is just physical memory, if you want to check the virtual memory occupied by certain software or system component, then you’d have to use some other ways. If you use Windows 7 system, then you can directly see it in task manager.
 In Windows 7 system, press Ctrl+Shift+Esc combination to call up task manager, switch to “Process” label and click “View—Choose column”. And on the opened window “Choose process page column”, check “Memory-submit size” option, after succeeding the modification, call up task manager, the column “Submit size” is the virtual memory mentioned in Windows 7.