The computer does not boot up at all nothing comes up on the screen I have changed the power supply and the ram also disconected all the hardware and still no boot up. what do you think john

If it wont POST-then prbly hardware problem-inspect MOBO -disconnect all drives and try to boot into BIOS

your problem could be almost any of your hardware components
the best way to detirmine wich one/how to fix it is with a process of illimination. You should do this by switching your hardware components with known good ones.
being a display problem the order i would test with is this.

1. disconect everything but the screen
2. swap screen for a known good one
3. disconect graphics card and try the onboard (if no onboard try another gc)
4. test psu (power supply unit) this can be done with either a psu tester, multimitre or try with another psu
5. try removing all your RAM, when you boot if your system beeps a couple of times you know that your motherboardand cpu are good. if it doesnt beep it is probably your motherboard or cpu.
   

Sometimes when you use ram sticks on some older computers they do not handle taking teh ram stick out of the USB port without first closing out teh device OR if you have the RAM stick in while you are booting the machine... it will select the ram stick as the boot device and appear there is no oprerating system present.

In you case when you go to the boot menu.. be sure the boot menu is set to select the hard drive as the primary boot device. If it is not then you can make the change at teh bott up screen.

your power supply ( inside the computer) sounds to be faulty have it checked .

what u may have done is wwhen u were installing the new board, gave a static shock to the system...that will cause only the fans to come on and nothing more...this is a bad problem bc u cannot fix it...if u figure out something else is wrong, and it gets fixed, let me know

have u tried booting the computer with just the power supply hooked up and your battery out? iv'e had the same exact lab top and the battery went bad and the computer wouldnt do anything at all like your talking about. Even if i had the power supply hooked up and the battery. Remove the battery, and try booting it up.

check whether the switching on button works correctly...or check whether the power supply is normal from SMPS

No bios no post and no power lights on disk drives means hardware problem.

Either call a technician or try the following if you feel you can do it yourself, beware , there is always risk of damaging your PC on DIY.

unplug the computer, open PC and remove all plugs and internal and external devices, leaving only a minimal set of devices.

Start the motherboard with only Power adapter , one RAM module, and video card and screen connected. Unplug all disks and external devices, remove all pci cards.

If it still does not start take it to a repair shop, you may need to replace power supply, motherboard or ram.

you need to take every ram, board and cable out of place... then clean it all perfectly... (isopropilic alcohol is the best to use in cleaning hardware) then reconnect it all and just try powering on with just motherboard, cpu and ram, NOTHING ELSE... if the system starts... you must connect all pieces, one by one, booting the system after includding each thing to isolate the problem if there is one... after all peaces are back togeter, test the system normally.

IF MOTHER does not boot only with cpu and ram... you have hardware problems either in mother, ram or cpu or power supply and you will need to replace hard... good luck

Hi there. It would help if you provided more info regarding your problem. The follwing would be good startpoints:

1. What was the last time you were able to do with the laptop?
2. Have you made changes [immediately] before the issue started happening?
3. How old is the PC?
4. What are its specifications (ie.CPU speed, memory type and size, OS, etc.)
5. Have you experienced this same problem before using the same computer, or on another computer?

Well, here's a shot in the dark. If the unit is, say more than 5 years old, it's probably a hardware defect. Meaning your unit's screen display data connection is already out of order. This usually happends to laptops with data connections too compactly embedded between the hinge of the laptop lid and chassis.