>>550169can't tell from pic if desktop monitor or laptop screen
>is thermal paste any good?hwmonitor will tell you temps
did you wipe it clean before applying? did you firmly press the heat sink against the CPU? if it's floating on a blob of thermal paste I've got bad news for you: thermal paste is meant to cover spaces, not as the main heat conductor. main heat conductor is metal-to-metal contact. also are the fins near the fan clean? if they're covered with dust, heat transfer will also suffer. compressed air to flush out.
also task manager
right-click taskbar to get to it
what's taking up disk usage? what's taking CPU usage? click top of column to list by order of selected column.
look at event viewer. control panel, administrative tools, event viewer. any error messages? some are generic (google them). more concerning would be disk errors or bad blocks.