Вы можете сделать это, используя WMI :
Dim devlist as object
Dim dev as object
Dim totalRAM as long
Dim numChips as long
Set devlist = GetObject("winmgmts:{impersonationLevel=impersonate}").ExecQuery("SELECT * FROM Win32_LogicalMemoryConfiguration")
numChips = 0
For Each dev In devlist
numChips = numChips + 1
totalRAM = totalRAM + CLng(dev.TotalPhysicalMemory)
Next
devlist = Nothing
MsgBox "RAM: NumChips = " & numChips & ", Total = " & (totalRAM / 1024) & "MB"