Computer turns on but i get a black screen

[Murder68]

I can't manage to get windows to boot,I can hear the fans spinning and the power LED is working,but my monitor LED is flashing and i get a black screen.
This problem started about two weeks ago,usually I would unplug the power cable from the computer and hold the power button for a few seconds and that would solve the problem,but now I just can't manage to get a display.
The PC also turns off after i press power button once,usually it takes about 5 seconds.
I tried unplugging some components,like my storage HDD and my disk drive,also trying reseating my GFX card and my RAM,neither helped.
Help?

specs:

Asrock H61M-HVS
Radeon 6850
XFX 450W PSU
4 GB kingston RAM
Core i5-2400
Two 7200RPM HDDs

 

[suteck]

First thing I would try is using the ondie video if your cpu is capable, you didn't mention which one you have in your specs so I'm not sure. Pull the video card and and try it that way. Double check cables, make sure the video card has the 6 pin power connector attached securely and that both the 24 (20+4) pin power connector and the 4 pin power connector are attached to the motherboard. If all that check out and you still have problems I suggest you follow the link under my signature for fixing "no video" problems. Take your time and go all the way through it step by step. Don't skip them because you think you already know. Double check according to the checklist - that's what helps. If not of those things work or even if they do let us know how it's going so we can help if still needed.

Check on the power supply required. Here is a calculator - http://images10.newegg.com/BizIntell/tool/psucalc/index.html?name=Power-Supply-Wattage-Calculator - just put your specs in. The 450 in the minimum recommended but sometimes it comes down to whatever else you have in your machine.

 

[Murder68]

Can't believe i forgot the CPU,added.
Thank you for that link,it was very helpful.
So after several tests I am 90% sure that my monitor is the problem.
I managed to run my PC on 2 other monitors both with and without the video card on both DVI and RGB.
I tried connecting a different PC to my monitor with an RGB connection and i got no display.
However,after turning off my PC and unplugging the power i can still get the lights to turn and the fans to spin for a couple of seconds if I press the power button,which causes me to believe that the problem still exists and is in my power supply or motherboard.
I don't have any spare MOBOs or PSU to test with,but I do have warrenty (although I'm doubtful they will perform any additional tests and I can't be arsed to drive all the way to the store)
So my question is,did i solve the problem or is that small power surge standard in computers? I'd hate to buy another monitor only for it to die with my PC (which is actually just 6 months old)
Also, Is it normal for a monitor to die in 4.5 years?
sorry for my ignorance

 

[suteck]

You will always get this - "However,after turning off my PC and unplugging the power i can still get the lights to turn and the fans to spin for a couple of seconds if I press the power button,which causes me to believe that the problem still exists and is in my power supply or motherboard". That is the residual energy stored in the capacitors and other electronic components in your system. It's normal and not a cause for alarm. That's one reason you're always told that "after unplugging the power cord from the wall make sure you push the power button for a few seconds to remove residual energy before removing any components" statement. So I would say the problem seems to be solved.

As for the monitor dieing in 4- 5 year??? there are so many variables no one can say.

 

[Murder68]

Best answer selected by Murder68.