some thoughts
try booting in safe mode (hit f8 before windows screen pops up. select safe
mode without network support) The more stuff that is wrong- the longer it
takes to boot up- as some stuff is getting corrected along the way. This
starts up without drivers- so you can't go online, some software won't work,
etc.
2 less likely- use a program like malwarebytes.org to clean out spyware,
adware, trojans.
This is just in case any of these guys are fighting for memory space at
bootup and during a warm reboot, the second guy in line no longer has a
problem... goes to another place, etc. If you shut down cold for 15-20
seconds does this problem repeat? if so, may be malware. If it does not,
could be hardware- warm hardware in a cold-power up state might not be as
difficult as colder hardware.. this might help differentiate. I always use
a 20-60 second powerdown to diagnose problems (temporary memory resident or
more hardware-based- and then overnight vs 60 seconds to see if its
temperature related and symptomatic of an impending larger scale failure)
3: off-topic: My wife's computer was so slow it took 30 seconds for Internet
explorer to start and another 30 seconds to bring up msnbc.com as the start
page. There was no load on the CPU so it was puzzling- I did all the usual
cache cleaning, etc- not much improvement.
I used advanced system care from Iobit labs and it found 3 remote background
processes (obviously part of a botnet for spam or filesharing- some other
thing- using my wife's computer for bandwidth.)
It shut down the processes and open ports where no others found it- and the
computer speed recovered quickly.
4: the usual cleaning stuff as others detail.
regarding hot and cold booting and overnight vs 60 second shutdowns:
a: a weak electrical connection that when stuff warms up - a better
electrical connection is made. Eventually there will be a failure. I had a
drive that was suspected to be failing and in swapping them around,
eventually figured out one side of the power supply was starting to deliver
substandard voltage- hence irregular success with bootups. (I use
motherboard monitoring software now to keep an eye on voltages and temps)
b: a hard drive that is sticking or erratic and takes a while to become
operational- like once it warms up. could be a sign that a bigger HD failure
is coming soon
