My computer turns on, but nothing comes out on screen

This problem may be caused by several things. usually we check connections, memory ram, memory slots, and the last thing we check are the voltages from the power supply. really this should be the first thing we need to review.

Connector pinout for: ATX - BTX Motherboard Power - 24 Pin.

In many cases the source of the problem is a faulty voltage from the power source.

measuring with the tester the voltajes must be:

How do the measurements?
A tip of the tester in any of the black pin, and the other in the pin we want to measure.

The Most power supplys have a tolerance of 10%.

Presario f700 with cpu overheating.

I have a Compaq Presario f700 and the speed of the system is always extremely slow, I uninstalled some heavy programs and yet it is still slow . The CPU has a temperature of 90 degrees. I have a 120gb Hard drive and a 1gb Ram. I am running windows XP professional Service pack 3 with an AMD Semprom(tm) and a 32-Bit operation system. Please help!


Solution:

well my friends ... first of all we must check the temperature of the cpu. For this there is a program called Notebook Hardware Control (NHC). You can download it from the site www.pbus-167.com.

The maximum temperature for an AMD Sempron is 85-90 degrees. At this temperature the pc starts to crash and reboot. The temperature reached was 84 degrees. We checked the fan and it is working properly. The next step is to open the laptop and check the cooling system.

This is the service manual for presario F700.
http://bizsupport1.austin.hp.com/bc/docs/support/SupportManual/c01295900/c01295900.pdf

and this is the laptop disarmed:

We check the cooling system and we found covered the air outlet:

then We clean the fan and airflow chambers and we assemble the laptop. Then turn on the cumputer and open some programs to force the cpu. Immediately open the Notebook hardware control and monitor the temperature, it should not exceed 68 degrees.

This laptop is working satisfactorily.

**Preventive maintenance is recommended at least every six months.