PC boots, but no display

[forfaden]

I am sorry if this is in the wrong category

Ok, I am having a problem with my computer. It seems to boot, but my monitors are getting no signal.
And it was working fine for about a week since I got it.

previous specs:
ASUS P8Z77-V LX LGA 1155 Intel Z77 HDMI SATA 6Gb/s USB 3.0 ATX Intel Motherboard
Intel Core i3-2100 Sandy Bridge 3.1GHz LGA 1155 65W Dual-Core Desktop Processor Intel HD Graphics 2000 BX80623I32100
COOLER MASTER Elite 311 RC-311B-BWN1 Blue Steel / Plastic ATX Mid Tower Computer Case
GIGABYTE GV-N210D3-1GI GeForce 210 1GB 64-bit DDR3 PCI Express 2.0 x16 HDCP Ready Low Profile Ready Video Card
Kingston HyperX Blu 4GB 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800) Desktop Memory Model KHX1600C9D3B1/4G
COOLER MASTER GX 450W RS450-ACAAD3-US 450W
(was gift, not built by me)
(also, he didn't include the motherboard speaker..)

Then my good friend updated his computer, and he had a ati radeon hd 4850 and he gave it to me.

So i took out my current graphics card and put the 4850 in there, plugged the power supply in there also.
Booted, went to windows, did the windows pc score to see how the new card was. (2 points higher than old one)

Then I get up to go get a drink and I come back. PC is off, I try to turn it back on and fans spin for maybe a second. Than I try again, no fans on.
So I put in the old one, still nothing.

Than I unplug everything from the power supply.
Set it sit for an hour.
Than I plug everything back in.
It does turn on, all the fans go and it makes some noise, but it does not display anything to the monitors I have.
I tried two different monitors, and i tried the 4850 ports, the old graphics ports, and the motherboard ports. Still got nothing from any of them.

What I have tried:
I tried both cards and the motherboard for video out.
I unplugged everything from power supply for an hour
I reset the bios
I tried both ports on the 4850
I tried every port with both monitors.

I know that I did install the graphics correctly because I ran from it for 10 minutes, and managed to get the windows system rating.
And it worked fine for a week before I put this new card in

 

[geekapproved]

All indications point to power supply.

 

[slcmike]

system utility monitor: http://www.cpuid.com/softwares/hwmonitor.html

- Power supply may be faulty. Make sure the fans on the pwr supply are spinning always and are not "weak". Does it get very hot quickly after start up?

- RAM issues: Intel scales ok with RAM rated at 1.6 - 1.65v but not having used Intel in a while I am not sure if its going to work well at 1.7v and higher. Use the HW Monitor and verify the constant voltage the RAM is running at. You may have to under clock the value to 1.5-1.65v in order for the system to run stable.

Let us know what you find, and we'll go from there.

 

[forfaden]

Even though the leds on the board light? and the fans go?

 

[xcrossroadsx]

The power supply is most likely the culprit, however may I suggest trying a different cable between the computer and monitor? If you are lucky and that's it, then it will save you some money.

 

[slcmike]

Even though the leds on the board light? and the fans go?

Just because the led is on and fans spin doesnt always mean there is enough pwr to push to the card.

 

[geekapproved]

LED's and fans use very little wattage, and not the same power source as the cpu and graphics.

 

[smorizio]

check the d-ram led is it green or red?? if it red it a d-ram failure or over clock failure. also check that no one moved the gpu over clock switch..by default it set to disabled. as you add a card you may have pulled the cpu fan wires out of the cpu or from the mb. if you did most mb wont post to save the cpu. i would also check that you did not get any wires into the gpu or cpu fan. if you did you may have sliced and shorted it out. if you think you got a wire in the fan of the cpu it may have over heated and shut off. with the power unplugged i would check to see if the ran all the way in on newer asus mb they use new type of clips to keep the dimm seated. i would also will the power off take a look on the video card and mb and see if you can see any burn marks. if there was a power issue you could have pop a chip it going to look melted or smell.

 

[forfaden]

The led is red, I wasn't sure if that was normal or not because I had never looked at it before.

And there was not a strong smell of fire or melted parts, I will check when i get home though.
And I had checked every single plug and cable on the pc. Also my processor does not support over clocking and there is not a switch for it on my board.

There was something odd about the seating of the ram, so that could be the cause, but it worked for at least a week, so wouldn't it have not worked then?

 

[forfaden]

Thanks guys, you were right. Power supply.

Got new one and it works perfectly.

 

[forfaden]

Best answer selected by forfaden.