HTC Desire HD Random Restart I have a HTC Desire HD phone, I installed "Android Revolution HD" and "BlackOut Rom" to it before, I made same overclock stuff... Now my phone restarts randomly, generally while connecting mobile network, if I make it AirplaneMode and only use for wireless network connection it works (but restart sometimes too), I watched debug strings with ADB but can't find why it keeps restarting... buy the way it is not restarts when in recovery mode...

So how can I understand what is wrong with my phone ? Where should I look ?, should I install a ROM from HTC to see if it is working right...
You could start by not overclocking the device. That's a common cause of system instability even in ROMs that are usually stable. If it's still unstable because of that, it could just be instability caused by (bugs in) the ROM you're using. Try flashing back to the the stock HTC ROM.

If it's still unstable after flashing back to the stock ROM, it could be that your overclocking of the device has caused internal components to overheat, permanently damaging them. One of the functions of the CPU power governor is to slow things down when the device is overheating. Overclocking the device, or using a custom ROM where the governor is replaced by a less cautious or buggy one, defeats that protection, risking that kind of damage. If that's happened, you probably need to replace your phone and be more careful next time.