I have the Presario F700. it wont turn on.
HP really messed up with some series of laptops that use amd processors and nvidia chipsets like the F500 and F700, in latin america, where I live, they never provided a solution and in the US, Canada and other countries a product call back was made but not all the users were informed and it's no longer in effect, so what you can do is repair your laptop, I'll tell you how.
You will need:
-presario F700 service manual (google it, you'll find it easily)
-heat gun or hair dryer
-thermal silicone grease
I know it sounds like something MacGyver would do, but it helped me with several presarios F500 that wouldnt turn on. I'll explain a little so you can see why this actually works. The computer will stop turning on, in some cases wi-fi will absolutely die before,when the computer overheats, to be precise, the nvidia video chip overheats the soldering that holds it in place, when contact is lost the problem appears. So what you need to do is simple, first you need to "re-solder" the chipset, then you need to improve the system to prevent the chip from overheating, thats when the penny is used, as it is made of copper (or so I was told, I'm not american so I couldn't say for sure) it will act as a heat sink for the video chip, copper has great thermal properties.
First thing first, you'll need to follow the instructions on the service manual to dismount the fan/heat sink assembly, be really carefull not to misplace any screw or you'll have a hard time putting all back together. There is a part of the service manual that will require you to dismount the display,carefull, the complete instructions regarding that part will lead you to disassemble completely the display, my advice is, once you remove the screws that hold the display to the rest of the computer you can continue with the top cover (where the touchpad is located).
Once you have the motherboard out, identify and remove the processor as well, the fun begins now, using your heat gun or hair dryer heat the nvidia video chip, thats the one by the processor not the one by the wi-fi card, if you use a heat gun heat it for about 2 minutes you wont need more than that, try to direct the heat only to the nvidia chip, you dont want to de-solder any other components, you can cover the rest of the motherboard with magazines, that helps a little, if you are using the hair dryer make a cardboard cone to redirect the heat to the chip, you'll need to heat it from 10 to 15 minutes depending on your hair dryer, make sure to hold the heat gun or hair dryer at least 4 inches away from the chip, dont apply heat directly.
Once you are done heating the chip, you'll need to press it firmly to put it in place again, you wont feel the difference but simply do it, dont do it with your fingers or you'll burn them, that should do the trick, your computer is now fixed, however if you put it back together just like that it will fail again soon, so we need to improve the heat sink for the video chip.
You need to use the thermal silicone on both sides of the penny, then put the penny over the video chip, as centered as possible and then put the heat sink back on, off course you need to put the processor back on before putting the heat sink back, there is an optional thing to do before putting all the rest back together, you can drill some holes on the base enclosure right where the video chip is located, that will improve ventilation, then follow the instructions to put all back together, after that you can try to turn your computer on and see it turning on like it used to.
This has worked for me several times, I hope it works for you as well, one last advice, update your bios to latest version and get a cooling pad to prevent as much as you can the overheating issue, good luck.