Mandy Louise White

Unit 311 Repair and Rebuild

Gap analysis

We determined that we were going to diagnose and repair a system that is located in the workshop on the computing floor. The system had two faults that I diagnosed before I could boot the system without failure. When tested the system had no RAM and no fuse was fitted in the power supply cable plug. Once these were corrected I was able to power up successfully. Before removal of any hardware make sure all connections and cables are secure so the problem can be eliminated step by step. Once you have determined the fault is not due to this and the system does not boot up or there is no power at all, then maybe the fault is caused internally. If this is the case then gather all relevant tools to diagnose and repair the system. In this case the solution was to replace or upgrade the RAM, because the RAM was not present then we did not need to upgrade but place a 4GB DDR3 memory into the DIMM slot on the motherboard. Without RAM you would not be able to boot the system successfully.

Mandy White

Customer

Fault validation

Information gathering No power to system on boot up FAILNo lights or error messages FAIL

System information MotherboardRAMPower supplyCPUSATA HDOptical drive

Error logs/Initial findings

Missing RAMMissing fuse from power supply cable

Name of customer Mandy White07673463234

Cost of parts 4GB DDR3 RAM5 amp Fuse for power supply cable

Evidence Acton taken RAM was placed into the DIMM slot but system did not power up once the cable to the power supply was checked it did not contain a fuse

Repair carried out RAM was inserted into the DIMM slot?? amp fuse was fitted into power supply cable plug

Date 27th February 2015

Signature

The first step for diagnostics is to make sure you follow all health and safety steps. Make sure the area you are working in has enough space and is free from cables, any liquids and there is plenty of room to place any parts that are removed from the system you are working. Check that you have the relevant tools to work with and any objects are not interfering with the repair.

Cross head magnetic screwdriver: most of the screws use this type of screwdriver and because the screws are relevantly small if they do fall inside the machine if the screwdriver is magnetic this will make them easier to retrieve

ESD/antistatic wrist-strap: this will ground you in case of any build-up of static electricity that occurs through fibres of clothes or any electrical surge from inside the system

Circuit Breaker: this will automatically switch off all power should there be an overload or short circuit and will detect any faults and interrupt the current flow

Overall: a white overall will keep you protected in case of damage to yourself and will show up any colorants

Hair bobble: to tie long hair back so it doesn’t get caught in any moving parts or get stuck in any parts and cause damage to the components

Are the circuit breakers plugged in ready to test the system when you have diagnosed the repair and you begin to test the equipment?

Before any attempts to enter the inside of a system or do any repairs place the anti-static wrist strap on your right wrist. This will prevent any build-up of electricity through your body and prevent any shocks occurring through the repair. This is an essential safety point to take.

Once you have checked that all plugs have been removed from the sockets (to prevent any electrical shocks) you can start to remove the casing on the system.

Once the case is removed and we have the view of the inside of the system we need to check that the CPU is secure in the socket. We then check to see if the RAM is secure in the memory slots. It is apparent that in this case the RAM is missing from the system. This will cause the system to fail booting up as RAM is required for any system to work.

I placed a 4GB memory module in the slot on the motherboard to see if this would fix the fault in the system. Once all the cables connected to power supply were checked they were connected to the motherboard I then connected the power supply cable to the back of the computer and attempted to power up the system.

Once a fuse had been checked to see if it was the correct voltage and fitted securely into the plug I then pressed the power switch on the system and powered it up successfully.

Circuit breakers are an important factor when working with any electrical equipment to make sure that if there is a power surge anywhere in the system. These two plugs are both connected to the circuit breaker. One is the power supply cable and the other is the monitor. Make sure that the circuit breaker is reset by testing the circuit breaker before you power up the system.

Once these steps were taken I attempted to power up the system but there was no power at all going to the system. The first step to take in this scenario was to check that the power supply cable was firmly connected to the back of the system if it is in this case the next step would be to check if the plug to the power supply has a working fuse. Once the plug was removed from the socket and I checked the fuse it was apparent the fuse was missing from the plug. It is necessary to have a fuse in any plug whether it would be a hair dryer or an iron, if the fuse is missing you will have no power and it won’t operate.

we were given the task of stripping the system to the bare minimal and identifying the components we were taking off the motherboard then step by step putting the system back to its original condition and being able to boot up successfully. My system contained the CPU with heat sink and fan which I took a photo of.

Do not attempt to remove the power supply unit from the inside of the system if any cables are connected. Once you have removed the power supply put it in a safe position clear from any liquids and out of anybody’s reach of damaging it. Use the appropriate screwdriver to ensure you do not damage any of the screws. If the screwdriver is too big for the screws it will damage the threads and prevent the correct screw from fitting.

The motherboard in my system had two memory slots for the RAM. I placed a 4GB stick of memory inside one of the slots at the start of my diagnostic process after discovering no RAM was inserted inside. The fan has a with four pin that connects to the motherboard

In this picture we can see the fan connector which powers the fan and is connected to the motherboard with either a three pin or four pin connection

Once the heat sink and fan has been removed from the CPU place it in a safe position away from any liquids and out of reach from damage.

The CPU is ready to be removed from the socket 7 that it is placed in. This is done by lifting the arm at the side to release the pins of the CPU and safely lift out from the socket.

Once the RAM has been removed from the memory slot on the motherboard place it in a safe position but close to the component’s that have already been removed.

Once all the components have been removed from the motherboard all that is left are the wires that are connected to the casing of the system, these are the power switch and reset which power up the system.

The case is now completely stripped of every component that created the system and we can begin to build the system to its original condition. It will be helpful for any future reference that at

this point you take a note of all the components that you have removed from the system including;

Motherboard model RAM size and manufacturer Power Supply CPU manufacturer and speed Hard Drive Optical Drive

Before I began to screw the motherboard into its position I connected the power switch and the reset wires back to the correct pins on the board because I have found in the past these to be quite fiddly and they are labelled on the board but if you have poor eyesight or large hands fixing these wires before placing the motherboard into position makes it easier.

Note in this picture that the arm of the socket is in an upwards direction when really it should be firmly put back into place because if you was to slip or place your hand on it, it could damage the socket or cause an injury.

All our components have been removed from the casing and placed in a safe position on the workbench to prevent damage.

In this picture you can see;

Power supply CPU and Heat sink Crosshead screwdriver SATA HD 4GB RAM

All that is visible in our case is the optical drive and the SATA HD.

Once the motherboard has been securely screwed into the casing we can now begin to put the system back to its original condition.

Our RAM and CPU is placed back into their correct slot and socket. The optical drive and the SATA HD have been placed back into their

correct bays. All the power supply connectors have been connected to the motherboard. In this case we had a 400 w ATX power supply.

Once the additional components were placed back into the motherboard I was able to boot up the system successfully.