When i power on my benq fp731 monotor it comes on then go's blank

When it have this kind of error is a problem of the powerboard.
Anyway you must open it and look at the all capacitors and if are them inflated, if them are inflated must change them.

But can be a problem with inverters... control the transistors - MOSFET on the powerboard.

Good luck!

Benq t720 inverter parblam plz repair

jsiwiec, Are you absolutly certain that the "cold-cathode-fluorescent-lamps" need replacing, or if the "switch-mode-power-supply"/"CCFL inverter supply" is not working and is in shutdown mode? CCFL's are not some kind of miniature version of those energy efficient screw-in new style, curlie-Q cfl light bulbs you buy at the local home-center!!! In any case here are some places to checkout first. www.ccfldirect.com ,
www.teliostech.com , www.ccl-la.com/badcaps.htm , www.lcdparts.net, www.lcdrepair.us You do know that most times the problem is not the lamps. Did your LCD display have bright, crisp, colorful images displayed on the lcd panel 2- 3 days before black screen happened? How many TOTAL "ON" hours of use on this BenQ FP731 ? When was unit produced? Good luck with repair. Hope info was helpful.
12fixlouie

Opening it will not likely solve your problem. Have you tried another monitor on the computer to see if the problem may be with the computer itself?

check your resolution settings and change to 800><600 and try again.If it does not work at 1024><768 try loading monitor driver In display properties it should show BenQ FP731 instead of plug and play monitor.
Samir

Just leave the monitor for a while about an hour and try connect and see, if not displaying than Try changing the display resolution from your laptop and see what happens.

The power and Inverter board has a problem.Check Inverter transistors and the related fuse.

Dor, BenQ has a 3yr warranty on their monitors. I would contact their tech support and receive an RMA to return it for repair. It will cost you shipping out there but they will ship it back. I has a BenQ FP731 myself and it blew a capacitor inside that allowed the screen to stay on. Fixed it and had it back in 5-7 days. Good luck.

Change the 2SC5707 transistors and electrolytic caps in the inverter
section. Also check the 3A picofuse, and resolder all transformer
pins

Looks like your Power Supply has gone Kaput .. Usually it is the Electrolytic Capacitors on the Power Supply Board, try a new one, or replace ALL the Electros with same or better ones.