Susan.A addressed the Office version
here.
RAM can be found in tblAssets (tblAssets.Memory), which is already part of that query.
Add tsysOS linked on tsysOS.OScode = tblAssets.OScode and you can pick up OS information.
Add tblComputerSystem and you can determine the OS bitness:
Case
When tblComputerSystem.SystemType Like 'X86%' Then '32-bit'
When tblComputerSystem.SystemType Like 'x64%' Then '64-bit'
Else ''
End As OSBitness,
Add tblAssetCustom to obtain the purchase and warranty dates.