No beep and black screen on startup

Hello,

Black screen issue on the first boot of the computer:

This tutorial is aimed at those who have just assembled a PC and thus it does not boot or the screen remains black. It is also for those whose screen remains black after a boot even if the setup has been running for years.

For those who have just assembled a fresh configuration:
I - the PC does not start at all:

1 - Check that the CPU fan is properly connected to the motherboard.
2 - Check that the power supply is properly connected to the motherboard and that the switch on the back of the power supply is set to 1. (The small switch at the back of the power supply (on/off)).
3 - Is the power supply connected to the mains?

? Normally the PC should start.

4 - Perform a CLEAR CMOS: what is that?!?

CLEAR CMOS: It’s resetting the parameters to default of the small program that allows your computer to boot.
To perform a CLEAR CMOS: on the motherboard, you will see a battery (round), target that area. Next to this battery, you have 3 pins (3 small rods) among which two pins are connected by a jumper.
Move the jumper to the other side, remove the battery, wait 2 seconds and put everything back in the order you want.
(For more info, refer to your motherboard manual).

? Normally the PC should start.

II - the PC starts but beeps and/or I have a black screen:

The recommendation is to test the purchased configuration with the minimum number of components to better target the cause of the problem:

If it starts but with a black screen and/or beeping(s), we know from experience that the following components are usually problematic:
A - RAM
B - Power supply
C - Graphics card
D - Motherboard or processor.

So if the PC, once assembled in the case, shows a black screen even though the fans are running and is beeping, apply this:

A small note: be sure that the screen works properly. This means it does not have a cable issue (faulty DVI or VGA) that causes the screen to remain black. If you are unsure, test your screen before proceeding.

1 - Take your tower in front of you and only leave connected:
- Motherboard + processor + its fan;
- RAM;
- Graphics card;
- Power supply.

2 - If the PC starts:
Reattach the components one by one and start the PC with each addition of hardware to identify the faulty part to replace.

3 - If it does not start:
We will see as mentioned above, the first part that usually poses problems:

THE RAM:

Go back to step 1 but try to change the RAM (with RAM from a friend or another of your PCs):

1 - Take your tower in front of you and only leave connected:
- Motherboard + processor + its fan;
- RAM (from another PC or a friend);
- Graphics card;
- Power supply.

2 - If the PC starts:
It’s that the RAM is:
- Incompatible (unlikely);
- Faulty (most likely).

Change the RAM and reassemble the PC.

3 - If it does not start:
We will see as mentioned above, the second part that usually poses problems:

THE POWER SUPPLY:

Go back to step 1 but try to change the power supply (with a power supply from a friend or another of your PCs):

1 - Take your tower in front of you and only leave connected:
- Motherboard + processor + its fan;
- RAM;
- Graphics card;
- Power supply (from another PC or a friend).

2 - If the PC starts:
It’s that the power supply is:
Not powerful enough (unlikely);
Faulty (most likely).

Change the power supply and reassemble the PC.

3 - If it does not start:
We will see as mentioned above, the next part that poses problems:

THE GRAPHICS CARD:

Go back to step 1 but try to change the graphics card (with a card from a friend or another of your PCs):

1 - Take your tower in front of you and only leave connected:
- Motherboard + processor + its fan;
- RAM;
- Graphics card;
- Power supply.

2 - If the PC starts:
It’s that the card is:
Faulty (most likely).

Change the card and reassemble the PC.

3 - If it does not start:
We will see as mentioned above, the next part that poses problems:

THE PROCESSOR or THE MOTHERBOARD:

At this stage, you may have heard during the various startups of the PC, the motherboard beeping (once or multiple times):

Hypothesis:
- If it beeps: the motherboard is probably not faulty;
- If it does not beep: the motherboard is probably faulty.
To confirm these hypotheses, we will proceed as follows: we will test the configuration outside of the case:

1 - Assemble these parts outside of the tower (e.g., place the motherboard on its cardboard box):
- Motherboard + processor + its fan;
- RAM;
- Graphics card;
- Power supply.

PS: To start in this configuration step, you see that the case is not connected to the motherboard, so there is no possibility to use the POWER button of the case to start the configuration outside of the case.
Tip: - Take a screwdriver and make contact between the two poles (pins) on the motherboard where the POWER button should connect.
- Or connect the POWER button of the case to the motherboard (bulky).

2 - If the PC starts:
It’s that:
The case is haunted (unlikely)
The assembly needs to be redone in the case and there will be no more issues (most likely).

3 - If it does not start:
Redo the assembly of the couple: motherboard - processor - heatsink.

If the PC starts:
The assembly needs to be redone in the case and there will be no more issues (most likely).
If it does not start:
- If the motherboard beeps: the processor is faulty.
- If it does not beep: the motherboard is faulty.

For those whose PC was working perfectly until now and suddenly shows a black screen:

1 - Open your case:

Remove and reinstall your RAM sticks.

2 - If the PC starts:
Great!
3 - If the PC does not start:
Check the power supply.

Remove and reinstall your power supply: essentially unplug all cables connected to your hardware (DVD drives, burners, hard drives, motherboard....).

2 - If the PC starts:
Great!
3 - If the PC does not start:
Check the graphics card.

Remove and reinstall the graphics card.

2 - If the PC starts:
Great!
3 - If the PC does not start:
CLEAR CMOS

Perform a CLEAR CMOS. (See Paragraph I for the procedure)

2 - If the PC starts:
Great!
3 - If the PC does not start: it might be the graphics card that has failed.

Try a new graphics card

2 - If the PC starts:
Great!
3 - If the PC does not start: it might be the screen that has failed

Test with a new screen

2 - If the PC starts:
Great!
3 - If the PC does not start: follow all the steps from paragraph II.