Hi i have a problem with my monitor when i turned

SOURCE: Screen color changes, white becomes yellow.

I think you need to clean your monitor inside of it, dust can conduct heat making the screen material active and creating the yellowish tint to the screen.

I don't think it's a connection problem, becuse it if was you would not see nothing on the screen at all but only one connection error message or like 3 colors.

so you have to open it and clean it I usally use a hair dryer to clean inside stuff or a paint brush.

try cleaning it, but if you have special screws that you have to take out from the monitor you then have to buy special tools for those screws.
I had the same problem right now with my monitor, it's 7 years old, and decided to get a dell flat screen 22 inch.
but that's what I think is your problem, it's either dusty or oxidized meaning different oils are layered inside on the circuit boards. which are like insulators

SOURCE: Blank screen, but has power

It is most likely a backlight that has burnt out or something else of the sort. You will want to call HP Support and explain to them of your troubles.

SOURCE: blank HP w1907

If the power light does not turn color and stay's green on startup, it is not a power problem. It is most likely the inverter. If the unit is in warranty, send it out ASAP. Contact HP customer care by email and have the issue logged in.
If in warranty, they will send you a box by FedX second day and have repaired.
This is a 19" monitor and will not be worth paying for repairs if not in warranty.

Testimonial: "I am very happy that this guru was able to concisely evaluate the problem from the information provided. "

SOURCE: screen goes black after 5 to 10 minutes of

there is a screen light board defective as inverter board. there are on the market, some inverter boards available to LCD Monitor, Check for diemen Company on this site: http://www.hrdiemen.es/products/esp/index_esp.php

SOURCE: do lcd monitors over heat and shut off screen

It is possible that your the lcd inverter board is failing or possibly the back light, i suggest taking the back cover off the monitor and checking the power board for leaking or slightly buldged capacitors, to spot this youll have a dark liquid traces on the cap or on the board, the top of the cap must be flat not bulged, if there are any they'll need to be replaced, you can get them from electronic stores like Maplins, and if you are able to use a soldering iron desolder the the ones of the board and solder the new ones on. Make sure you get the exact farad rating of the caps, it dosent matter to much about voltage as long as it is equal or above the voltage stated on the cap. Also insure that they are replaced the correct way around, check this before desoldering from board.

Testimonial: "JIM,i removed board and there was a bad cap. replaced it and i am in business. money is so tight, i would have done w/o. thank you, rick"