Flash then off

[strike-down]

I have an old dell 17" TFT monitor as a second monitor
(not sure what model it is) but this is an image of the model:

It turns on fine, and when its working, its fine. But after about 15/20 mins of use, the screen suddenly goes bright for a second, then turns off. What would be causing this and can it be fixed?? Thanks in advance

[alsenior]

it could be either a dying inverter board or ccfl

[strike-down]

Is it worth replacing the inverter board or the ccfl given the current price of monitors on the market?? If it is, then where can I get hold of these?