HP Compaq dc5800 microtower Won't reboot!!HELP!

[Leonardo27]

Hallo!

Today got from a good old friend a pc so i can start to game abit i heave upgrade the ram to 8GB DDR2 from Elixir and 2 HDD from WD 250GB windows 7 ulti x64 install no problem at windows update all ok as soon as i want to reboot after bios pos nothing... windows wont start enymore if i stop the pc from the power button and then start normally its all ok i did try to enable or disable some options nothing CLEAR CMOS still the same....so if anybody can help me with some suggestion i w8 appreciate it!!

HP s/n:  [Personal Information Removed] and p/n:  AJ408AV

EDIT!

CPU intel 775 core 2 quad q6600

GPU GT 210 1 GB

[TheOldMan]

It is not exactly clear but are you saying if you do reboot it will stop and not boot up - this is known as a warm boot.  And if you shut down completely and then boot up - this is known as a cold boot - it will boot up?

[Leonardo27]

Hy!

So NO wenn i start up normaly the pc its starting and its all ok so lets say i update the windows and its says reboot to take affect so u press restart windows close and and then restart affter bios pos normal comes the windows logo but the pc freez up!! the nif u power off the ON the pc its all ok tryd with more windows 7,8,10 and linux ubuntu and still the same!!

[TheOldMan]

So this only happens after Windows updates?

[Leonardo27]

Hy!

No its every time i try to restart the pc!

[TheOldMan]

I suspect a startup software is hanging.  Go into open msconfig and take out all unnessary programs from your startup list.

See if that stops the problem.  If it does then try adding one at a time until the offending program starts it thing again.

If that does not solve the problem, are there any USB devices plugged in?  If yes, then disconnect them until you find the one causing the problem.

[Leonardo27]

HY!

So did try it and still the same tryd with win10 win7 linux tryd other HDD and SSD and the same bios its v1.59 maybe that!!

plug out all cables just monitor and power plug still the same!!

[TheOldMan]

If it has this behavior with various OS's, then it must be a hardware quirk.  I cannot say what but either a power supply or capacitors on the motherboard would be a place to start.  Bad caps are hard to find unless they are bulging and can cause weird things until they get worse.