Originally Posted by AMD_man
If your PC boots itīs not a bad CPU.
You'd be surprised actually. I've seen a few bad CPUs in my day and they all booted. It would typically manifest in instability that lasted through replacing literally every part but the CPU. My favorite was a core 2 quad Q6600 back when those were the
CPU to have that would cause the keyboard to stop responding until a reboot. Unplugging and replugging in the keyboard didn't fix it.
Anyways back on topic. Like others said, that is a very high temp. Blow out the dust and make sure the vents are not covered while in use. CPUs will throttle themselves down in terms of speed to save themselves when they get warm which can lead to an artificially high CPU usage as well (since it's not running as fast, less load means higher utilization).
One of the biggest factors in bootup and chkdsk speed is the health and type of the harddrive itself. If both of these tasks are slow then issues are likely with the drive. In fact, CPU usage is comparatively minimal when running check disk compared to most other applications on your PC. If you're still running slow after blowing out dust then go out and get a hard drive diagnostic utility like seatools and run then. Also uninstall any unnecessary software and make sure you give your PC a scan with your anti-virus and anti-spyware software.