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Computer turns on but screen is blank

Oltmania129 asked
Medium Priority
Last Modified: 2010-04-26
Whenever i turn my computer on everything turns on except for my monitor. The fans are all spinning, the cd/dvd drives turn on and so does the hard drive. The monitor is connected to a PCI video adapter and the LED in front blinks green once when i turn the computer on and then stays that amber color so i dont know what the computer is doing. The motherboard, CPU, Memory, and Hard DRive are all brand new. I still need to install an OS but if the screen doesnt turn on i obviously cant do that. I cant figure out the problem because the monitor worked fine on my old computer.
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The monitor is not getting a video signal from the PCI video adapter. Change the slot of the video adapter, seating it firmly and then retry. Double check the monitor cable that plugs into the video card and just make sure all the pins are straight (just to rule out a bent pin deny signal throughput). Get your MB manual out and find the clear BIOS jumper. Clear it as recommended (normally moving the jumper from its 1-2 setting to a 2-3 setting for about a minute and then putting it back on the 1-2 setting and then try to boot). If it didn't work try and enter BIOS (press DEL or F1 or F2 - your manual should give you the correct key - about four seconds after turning the PC on). Just to see if BIOS will scan for default hardware and report a text screen to the available output source rather than to a default setting to AGP. Try this and let us know. mike
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Consult the motherboard handbook and see if you missed a jumper setting, and check you led, and power cables that run from you case to the Motherboard. Then install the ram, at this point this is all you would need along with the processor to have an operationnal computer. if you see the bios screen then your back in business.

Its a PSU Problem as Snowguy suggested. Just buy a larger Wattage of Fan made by someone good like Antec or Enermax.
Have you changed the type of memory or is it the same as the old?

A very common error is incorrect seating of memory modules or bent pins on CPU. Firstly, remove the memory module and make sure you reseat it 100%. If this fails to work, and the old memory is the same, swap them over. If you do not have the same type of memory to swap over and are sure your module is seated correctly, remove the cpu fan and remove the cpu. Look at the pins on the CPU and verify none of them have been bent. When you are happy all pins are ok, reseat the CPU and fan.

Now boot the PC and see where we are from there.

This is a PSU Problem. Memory problems will give a beep. Replace your CPU with a higher powered one from a good brand like Antec or Enermax.
Do we know that the Case speaker is working or are we making assumptions?

He hasn't been able to test this. But regardless. The speaker will only beep when it posts or when there is an error. No beep/POST = Defective or underpowered PSU.
You are starting to confuse me.

You say the speaker will only beep if there is a problem, but because there is no sound coming from the speaker, we are to assume the PSU is guff, regardless as to whether we know the speaker is working?

Snowguy did not suggest the PSU was the problem, he only gave a good response, giving a series of tests, the first being to check the Speaker.

The problem I have with the PSU theory is that all is working, apart from the Monitor (or Video Card), yet the monitor does appear to get it's "Initialise" signal, as stated by Oltmania129 - "The monitor is connected to a PCI video adapter and the LED in front blinks green once when i turn the computer on and then stays that amber color"

Does the PSU power the monitor also? If so, why do we not try and lower the load by powering the Monitor seperately?

No, the speaker only beeps during POST and if there is a problem DURING BOOT. Sorry for missing those 2 words off.

It doesn't initialise the monitor. When the monitor turns on, I assume he's just turning it on at the same time as turning the PC on. When you turn any monitor on it is active "green LED" in this case. It waits for something to output, if it receives no signal, it goes to sleep. "Amber light". So it is not initialising.

The PSU is one of the most vital parts of your system. When you press the power on switch, a small volt signal is sent through the motherboard to the PSU to power up. The Motherboard then tries to POST. It tests itself to see if its in good working order. This is heard as being successful by a single beep from the speaker or a random number of beeps if there is an error, the number of beeps reflecting what's wrong... but moving away from that. If the Motherboard is not receiving enough power, it says to itself, "I'll have another go". The Mobo will just sit there resetting itself over and over until it burns out over many years or until it manages to receive enough power to turn on.

As I said, WE CANNOT TEST THE SPEAKER, cos it doesn't power up. It doesn't power up, cos there is not enough power. Not enough power = Duff PSU. It NEEDS replacing with a good brand higher wattage PSU. This solves this problem every time with me and it will for him.

Its just a shame this post seems to have gone dead cos the author aint checking back.
I understand your point, but you cannot assume anything when it is not in black and white. The author states the monitor goes to green when the PC is switched on.

Personally, my monitor is never switched off, it remains in stand-by until the PC is switched on, hence my thoughts that the monitor is powered via the PSU or the monitor IS getting it's initialise signal.

I agree it does not help when the author does not check back.


Snowguy: The power supply is new also and it is 400W

I disconnected everything but the power to the motherboard, the pc speaker (which does work), the memory, and the video card and still no result. The power supply is brand new, it came with the case and i dont think there could be anything wrong with it unless it came defective. I tried to get the BIOS to come up by pressing delete at startup like the mobo manual stated but nothing happened. There is no sound that comes from the speaker when i boot and everything seems to be powered but the video card. I tried using a ADP video card also. It is a new 128MB ATI Radeon 9200 AGP 8x and that didn't work either. I have tried all that you guys suggested and nothing has worked yet.
Does your Power LED work on the front of the case?


*AGP Video Card


The power LED does work, Yes

Check the back of the power supply and make sure it is set to the proper voltage i.e 110/230

That is what was wrong in this case today.


If it is a PSU that came with the case, then it is generic and not worthy of being in a system such as your own.

You need to replace it with a similar wattage good brand. Thermal Take, Antec, Enermax or Chieftec.

see gaffer ;)


Well i tried a different PSU and there was still no result so i figured the only other thing it could be was the mobo or the CPU. I was reading through the mobo manual before i sent it back and saw that it supports SOME DDR400 memory and not all so i figured that was why the computer was beeping when i turned it on. I went out and got some PC2700 and it works great. Thanks to everyone for their help!

doh. me = embarrassed now.

What exactly do you mean by "see gaffer;" ?

I think if you read through again, you may find that my initial suggestion was a memory issue, and lo and behold it was.

Nobody likes a gloater, especially when they have nothing to gloat about :)

Glad to see the issue is resolved Oltmania129, enjoy your new system.

well, u never said it was memory incompatibility, so you dont either ;).

Don't wanna make an argument m8, so leave it here, the question is PAQ.
Just messing with ye, Bud.

Happy to see the problem resolved.

Hey peeps! Can you help me? ..

Same problem really I turn my comp on and it turned itself off, The memory modules were not seated right so I sorted it out. The computer started and the screen was on. The BIOS then came up saying "During Last boot up your system hung got improper frequency comabtion" And sayings to change the CPU speeds and it was in safe mode. So I changed it to loads of speeds. With most it turned its self off but with one I got a blank screen but a loud beeping noise not coming from the speaks..

What do I do?

Don't use other peoples posts. Start your own question. This question is PAQ, therefor nobody wants to come back to it, because its already been answered. Experts hate it when people do this, so please dont and go and start another question. If we waste our time answering this, then we get no points.

But, just reset your CMOS, that should sort it.
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