The maximum recommended temperature for this processor is 72.6 degrees Celsius, so 73 degrees Celsius is OK, as long as it does not increase higher than that for long periods of time.
Please check this link for maximum recommended temperature:
If you are using the stock Intel CPU cooler, and don't have good case ventilation, then your temps are to be expected, but could be better. You need to read the mother board manual about the UEFI/BIOS, and adjust some settings to lower that temperature. It seems you do not have any of the CPU power saving options on, which are still useful if you over clock. You may also not have the CPU fan control software configured appropriately, which is also explained in the manual. I also suggest that you check the ASUS forum for your mother board, which will be much more help to you than this site.
I'm not sure where you are seeing those CPU clock speeds, but those figures are the usual Turbo CPU speed. On my ASUS P67 board, using AI Suite II, the TurboV tool is not a monitoring tool, but a voltage setting option available in Windows.
Since this is your first Intel CPU, I suggest you read as much as you can about it's features on this web site, and study the mother board manual to learn how to use all the CPU's features.