In Control Panel -> Hardware and Sound -> Power Options -> Choose what the power buttons do, then under the Shutdown settings section, Untick the "Turn on fast startup (recommended)". That's it! Apparently this setting is only used after a shutdown, so that is why after pressing the restart button it boots ok.Aug 16, 2015
Do I need to restart my computer multiple times to boot?
Bad power supply or inadequate power supply However, if you restart the computer a few times, because the platters are already spinning, it can sometimes boot. ... For most computers, we recommend you have at the least a 300 to 350-watt power supply.Jan 24, 2018