Install Windows 7 on a PC having less RAM
From the installation sources folder search for a file named winsetup.dll. Move it to your desktop, and make sure you make a copy of the original dll file. Download a free hex editor like HxD. There are many other good freeware hex editors available too. Open HxD as Admin. From its toolbar, click File > Open. Open winsetup.dll. Now search for string : 77 07 3D 78 01.
Change this hex string and replace it with: E9 04 00 0 00
Save this modified file. Exit. Replace the original winsetup.dll in the ISO, with this modified version. To unlock all Windows 7 SKU’s, delete ei.cfg file. Run setup.exe or burn the ISO to disc. Expect the performance to take a hit.