No picture can be seen on the LCD screen

Here I have three large red vertical lines at boot time and "pollution" in the form of a multitude of small horizontal lines. When XP is loaded, it turns into a multidimensional red square. After having set the resolution everything was OK, but after 5 to 6 minutes return lines and red squares. I connected a VGA screen but got the same defects. Loading new drivers for GC but nothing works and then back to former. I have also updated the BIOS but no improvement. I have tried many things but no picture can be seen on the LCD screen.

Indeed after we have tested that you describe I would say it is the graphics card is HS. Test with another test if you have the opportunity for that. And I also want to know few things about it that what is your PSU? Is the model single or dual slot? Your tower is well ventilated or not?
Is it still under warranty not? Because, if it is still under warranty then it will better to replace the system.

I tried another graphic card. Regarding the power supply, it's a Corsair VX 550, 12V single rail, and my tower is ventilated from front and rear, most of the time the hood is open. The graphic card is no longer under warranty, the rest yes.
I reinstalled after formatting with an iso image of my config. To see if there are conflicts between drivers RADEON HD4850 and older who were lying in various iso image, I will either reinstallation after formatting with either the XP CD or make a phone drivers cleaner.

I just equipped myself with TV PHILIPS FULL HD 47PFL5604H model and a HP DV7 2030 laptop and I connected the two via the HDMI having followed the instructions, and now I having a small display.

Indeed, if the picture is flawless and the sound, I found that more than a dozen times during the vision of a film there as an effect of stalling for a second or two (the screen becomes all black). This is not troublesome, but sometimes the image does not comes back to normal but I can see the colours are de-saturated image.

I am then forced to change the source and then return to the HDMI source to the computer screen is normal again.

Have you any idea?

At first, you must go to the manufacturer's website in the section devoted to your model. Then just click on <Assistance>, and then select the item and <Third-party pilots> where you will find an updated firmware for your TV. If this does not fix the problem, it should be noted that failure to Philips by email. I am sure you will get the solution for the same.

Thank you for responding so quickly. I thought it was just an adjustment to make from my pc. On the other hand, I tested my PS3 on the same HDMI and have found no issues? I do not think it is a simple setting? In any case I am already following the instructions at Philips regarding the connection of a computer system.

However, this bug may have already been identified and corrected. This would be a good starting point. I do not think too much of a problem adjusting because if the TV does not support a resolution, it shows on the screen with a message. One hypothesis that is the TV software does not yet support the resolution change. In fact, some video playback software changes the resolution in full screen.