PC is not booting up.

Hey,today I changed my CPU heatsink and started PC and it has gone through following phases since then :-(

1.First it started normally except Monitor was ON but wasn't showing anyting
2.At some point after a bit cleaning and reconnecting wires,I was able to get OS choice menu.I selected Vista but nothing happened (It happens to Vista sometimes while booting for first time on My PC) so I restarted PC
3.After restarting phase one continued.
4.I removed all chasis fans and DVD-RW and tried again
5.Then It started restating continuously.(LCD Monitor showed No signal Message and turned off).I removed RAM and checked and it did its usual warning sound,then I removed Hard disk to see If at least it shows me Insert correct boot disk message or not.
6.Since then it is not starting Mo/board is on,Cabinet LED is Glowing but Fans are not running
What should I do?

1. Check the graphic card
2. Make sure the disk is not there on the hard drive nor any external hard disk/ flash drive is connected. Change boot priority to hard drive on the bios.
3. Its kinda hard to give you a pretty good idea about the possible cause of the issue without knowing your system configuration.
4. .....
5. .....
6. ...
Possibilities is endless- without your system configuration being put out over here, you are going to get a pretty vague advice.

Config is
C2D E 6550[2.33]
DG33FB
2 GB Transcend
WD Cavier 250 GB
19" Viewsonic
iBall UPS

There are no fans spinning though LED on MoBo is illuminated

B

Techn0crat my pc is also behaving simliar to your...Luck maybe!

plz also see my thread post as "Motherboard help needed! Urgently" regarding similar situation. When I power it the PSU, CPU, GPU fan just turns 2 to 3 time then complete stop. No lights on front planel of the case, just hangs their and nothing.

Eh? The fans ARE supposed to spin to supply fresh air or the system will obviously overheat. You havent mentioned the power supply though. Check your connections with the fans. If they dont work replace the fans, but before you do- let me know the psu.

One of my friend told me that it's problem with my Processor.
And I haven't seen such problem except with my own PC
PSU is 450 Watt Circle(with cabinet)
There is definately no problem with PSU as I tried someone else's PSU but problem still continues.
It is either Mobtherboard or CPU problem.

Check the heat sink and the fans. Also check if the RAM is inserted properly.

Rohit Manglik said:
1- reset bios
2- change boot priority
3- use Linux live cd to check what is wrong with ur pc.

How can I reset BIOS?I can't even start PC.
Must find someone witd C2D to test if it is problem with MoBo or Processor