If i on it will off after 30minutes i put all the thermal paste in the processor and i fix also the heat sink but still it will off

check the processors heat sink. if it is too hot then it is overheating.
buy a small amount of thermal paste. remove the heatsink together with fan from the processor. remove the gray or white color like grease. clean it then dry. put the thermal evenly unto heat sink and top of processor. put back heat sink and fan. then test run.

INSIDE A COMPUTER OR THE HEAT SINK FOR YOUR COMPAQ COMPUTER?

The "CPU" or central processing unit, otherwise known simply as "the processor," is the primary "brain" of the computer. Processors are very finely engineered components that are not repairable. But replacing a failed processor is an option for the owner of any model Compaq Presario desktop computer. Just check with HP/Compaq for the correct and speed of processor for your motherboard before purchasing a replacement.

Turn off the computer and disconnect all cables. WARNING: Before you start troubleshooting remember that you are dealing with electricity that can KILL. http://www.kitchentablecomputers.com/static.php - rules Only work inside the computer case when the power has been switched off and disconnected. Never open the power source. Some of the below steps recommend removing physical parts within the computer. While in the computer it is highly recommend that you be aware of ESD and its potential hazards Remove the cover. Lay the computer down flat. If there is a plastic hood covering an exhaust fan, remove it by pressing in on the indicated release tabs. Examine the processor assembly. The processor is a square chip that is covered by a metal heat sink with fins. A fan will often be mounted on top of the heat sink; unplug its connection to the motherboard. Two clips usually secure the heat sink assembly to the top of the processor. Gently press down and slightly away on the flat end of a clip to release it. Avoid using a screwdriver to release a clip; a slip could scratch the motherboard. Release the clips and gently remove the assembly. The heat sink should separate, leaving the processor behind in the chip holder. Clean the bottom of the heat sink. Use a paper towel and a dab of solvent cleaner to remove the old thermal paste. Set the clean heat sink aside. Lift up the lever to unlock the old processor and remove it from the pin mount. Insert the new processor chip. Align the pins on the processor to the "cut off corner" or dot on the pin mount. The processor should drop into the pin holes easily. If the processor won't drop in easily, check the pin alignment. Once the processor is inserted correctly, pull down the lever to lock in the chip. Apply thermal paste to the bottom of the heat sink. Apply enough paste to cover the area of the small gray rectangle on top of the processor. Apply the paste with a spreader made from a piece of flexible plastic. Spread the paste evenly to a thickness of two sheets of paper. Check the heat sink mounting alignment and lower the heat sink onto the top of the processor. Reinstall the mounting clips. Reattach the heat sink fan to the motherboard if necessary. Plug in the computer and monitor and boot. If the machine won't boot or it emits warning "beeps," unplug the power and monitor, and troubleshoot your work until the computer boots successfully. Shut down again and replace the exhaust fan hood. Close up the computer and reboot. Hope this helps.

http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&DEPA=0&Order=BESTMATCH&Description=thermal+paste

WARNING: Before you start troubleshooting remember that you are dealing with electricity that can KILL.

http://www.kitchentablecomputers.com/static.php - rules

The "CPU" or central processing unit, otherwise known simply as "the processor," is the primary "brain" of the computer.

Processors are very finely engineered components that are not repairable.

But replacing a failed processor is an option for the owner of any model Compaq Presario desktop computer.

Just check with HP/Compaq for the correct size and speed of processor for your motherboard before purchasing a replacement.

Turn off the computer and disconnect all cables.

Remove the cover.

Lay the computer down flat.

If there is a plastic hood covering an exhaust fan, remove it by pressing in on the indicated release tabs.

Examine the processor assembly.

The processor is a square chip that is covered by a metal heat sink with fins.

A fan will often be mounted on top of the heat sink; unplug its connection to the motherboard.

Two clips usually secure the heat sink assembly to the top of the processor.

Gently press down and slightly away on the flat end of a clip to release it.

Avoid using a screwdriver to release a clip a slip could scratch the motherboard.

Release the clips and gently remove the assembly.

The heat sink should separate, leaving the processor behind in the chip holder.

Clean the bottom of the heat sink.

Use a paper towel and a dab of solvent cleaner to remove the old thermal paste.

Set the clean heat sink aside.

Lift up the lever to unlock the old processor and remove it from the pin mount.

Insert the new processor chip.

Align the pins on the processor to the "cut off corner" or dot on the pin mount.

The processor should drop into the pin holes easily.

If the processor won't drop in easily, check the pin alignment.

Once the processor is inserted correctly, pull down the lever to lock in the chip.

Apply thermal paste to the bottom of the heat sink.

Apply enough paste to cover the area of the small gray rectangle on top of the processor.

Apply the paste with a spreader made from a piece of flexible plastic.

Spread the paste evenly to a thickness of two sheets of paper.

Check the heat sink mounting alignment and lower the heat sink onto the top of the processor.

Reinstall the mounting clips.

Reattach the heat sink fan to the motherboard if necessary.

Plug in the computer and monitor and boot.

If the machine won't boot or it emits warning "beeps," unplug the power and monitor, and troubleshoot your work until the computer boots successfully.

Shut down again and replace the exhaust fan hood.

Close up the computer and reboot.

http://www.hardwaresecrets.com/article/Thermal-Compound-Roundup-February-2012/1490

Hope this helps

Hi,
Make sure that the fans are working at proper speed (not stuck or slow).
Secondly, heat sink could be clogged due to dust or not properly seated. Clean it if required. You may remove it, clean its fins and replace it back (for both processors if required) . Don't forget to apply THERMAL PASTE between the heat sink and the processor (If you remove the heat sink). The Thermal paste conduct the heat from the processor to heat sink which is then dissipated into air by the processor fan. You may also consider adding an additional fan, if required.

Also, place the PC at a well ventilated location so that the cool air enters it from the front and warm air leaves from the back.

The only thing that you did not mention was fresh conductive thermal grease compound, did you take the heat sink off the processor ic and remove the old thermal compound? if you have not done this you will need to complete the repairs and apply fresh conductive thermal compound this will dissipate up to 50% of the heat and should solve your problem. If this fails you need to make sure the processor cooling fan is running properly, or the processor ic may need to be changed because of thermal runner way.

Yes, and this is to promote better thermal transfer between components.

According to studies:
Thermal grease is primarily used in the electronics and computer industries to assist a heat sink to draw heat away from a semiconductor component such as an integrated circuit or transistor.

!!!Warning!!!
Over time, some thermal greases may dry out, have reduced heat transferring capabilities, set like glue and make it difficult to remove the heat sink. If too much force is applied the processor may be damaged. Heating the grease by turning the processor on for a short period often softens the adhesion. It is recommended that thermal grease be re-applied with each removal of the heat sink.

I hope it helped you. Rate for this information will greatly be appreciated. Thank you!

It is important to use good quality thermal paste like Arctic Silver. You only need a very small amount on the heat sink. Too much is as bad as none at all. You care just trying to create a thin layer of thermal paste to fill in the tiny gaps between the processor and the heat sink. If this does not help an aftermarket heat sink with more fins and a better fan might be needed.

check your thermal paste... buy thermal in the computer store, possible your thermal paste already dry and did not transfer heat at heat sink...

can you adjust your speed FSB jumper to reduce the processor speed.

apply your heatsink paste in your processor