mike1984 22:26 07 Mar 2009

Hi have a desktop when i switch it on nothing happens although fans etc power up there is nothing on screen screen says no signal and goes back to standby any ideas?

  woodchip 22:32 07 Mar 2009

Power Supply gone. it takes nothing hardly to power fans and put a little light on

  mike1984 22:37 07 Mar 2009

how can i test power supply?

  Fruit Bat /\0/\ 22:59 07 Mar 2009

click here
click here

If renewing a PSU check:

1. The physical size of your PSU, some are hard to replace due to being a non standard size.
2. The amount of power need from the PSU don't skimp.
3 The correct connections for your equipment

1. Physical Dimensions

Besides the specs and form factors, the physical dimensions are also important factors in selecting a compatible power supply. Here is an outline of the physical dimensions of most standard power supplies:

# ATX: 6x3.5x5.5", HxWxD. Most common. Uses 4 mounting screws.
# Mini-ATX: 5x3.5x5", HxWxD. Rare size. Uses 4 mounting screws. Can be used in a regular ATX case, but often not the other way around.
# MicroATX: 5x3x4", HxWxD. Use 3 mounting screws. Not interchangeable with ATX or miniATX.
# Flex ATX: Even smaller than Micro ATX. Various sizes according to case specs; often not interchangeable.

Use the data above to determine if a particular power supply would fit your case.

The quality of a power supply can be estimated by its weight. While this is not a true scientific or thorough measurement of the power supply reliability, it is nevertheless a very simple and easy way for ordinary PC users to estimate and compare the quality of a power supply. Why weight matters click here

2. Power supply calculator click here

3. Correct connections
Some boards have 20 pin connectors others 24 pin
There is often a 4 pin plug required to power Intel CPUs
Molex D plugs for IDE HDD and CD/DVD drives
SATA power connections for latest HDDs and DVD drives.

Guide to changing PSU
click here
click here

  DieSse 23:00 07 Mar 2009

"how can i test power supply?"

By changing it for another one.

But a faulty motherboard and other things too may show the same symptoms.

Commonest in my experience, in order are



Power Supply

Cables - poor contacts

Plug-in board.

  audeal 23:36 07 Mar 2009

Graphics Card may have packed up on you. If so a new one will be required.

  mike1984 17:07 08 Mar 2009

have put multimeter onto outputs from power supply all running on 12v and 5v any ideas?

  Fruit Bat /\0/\ 17:12 08 Mar 2009

PSU needs to be tested on load.

is hard drive heard to run? if not then PSU / motherboard dead

If hard drive running then graphics card us remove and refit for a start.

  mike1984 17:18 08 Mar 2009

something beeps when turn on not sure what it is though

  DieSse 17:29 08 Mar 2009

How many beeps - what is beep pattern - that may give an indication as to what's going on.

This thread is now locked and can not be replied to.

Elsewhere on IDG sites

Galaxy Note 8 vs iPhone X

This is what design agencies will look like in 2032

How to update iOS on iPhone or iPad

WhatsApp : comment lire vos messages sans que l’expéditeur le sache