I have power but it doesn´t turn on

These laptops are known for GPU failure, as are many laptops from this time period; I'm surprised it lasted as long as it did.

Hook the laptop up to an external monitor with VGA, since you'll need this to rule out the GPU. The typical failure mode is if it locks up under any sort of load, so what you want to do is try loading the OS normally. What I’ve noticed as the common red flag the GPU has died is when these laptops lock up when the high level driver initializes at startup. It’s even worse if it locks up sooner because that tells you it’s so bad that it doesn’t even work right with the low level drivers. If the laptop boots up correctly, the GPU is probably okay but the internal panel or inverter is bad. It’s almost always the GPU, so don’t hope for a miracle here.

If the GPU is bad but functional enough, you can boot into Safe Mode to recover the data from the dead laptop. On the other hand if the GPU is that cooked to death you will need to remove both hard drives (on equipped models; HDD 1 is usually data and HDD 2 is scratch space) from the laptop and see which one of the two (if a dual drive model) has your data. Once you get the data, either put the drive(s) into quality USB enclosures or destroy them if you would rather get rid of them. Do not bother repairing the laptop. These are DOA and perpetually die - even repaired.

Even if you have a newer model then these 2007 DV Series systems which are absolutely known to die for no reason, the later systems after this are just as infamous due to HP’s poor cooling decisions that didn’t die with the 2007 models.