This does not sound like an OS issue. Look at the usuals for machine repairs. If you feel it's the OS then review the machine's maker install plan. Be sure they note Windows 7 compatibility.
Again, this looks like an overheated CPU.
Bob
Hi, after installing the genuine pack of Windows 7 Ultimate 32 bit version my desktop PC performance slows down after sometime with slow videos and music, hanging up every now and then. Also the CPU and RAM meter given by Windows 7 ultimate shows RAM usage at 70-80% and processor at 100%. PC configuration: Gigabyte 8I945GZME-RH motherboard, 2.80 gigahertz Intel Pentium D, 16 kilobyte primary memory cache, 2048 kilobyte secondary memory cache, Board: Bus Clock: 200 megahertz, BIOS: Award Software International, Inc. F8 01/10/2007, ST380211AS [Hard drive] (79.88 GB), 1016 Megabytes Installed Memory, Realtek High Definition Audio, on board sound and graphics. No additional cards installed. The installation was a clean install. Any solutions?

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