Everything was ok... I was working on my Gauntlet Legends... I linked computer power supply cable & Speakers power cable to the existing Gauntlet Legends power supply... in order to use one switch to power on monitor, Computer & Speaker...
I power on after my work and :

problem on red color display -> a yellow area around the mouse


green also

For information i just use soldier near the monitor, but not so near ( about 50cm )... Is it the problem ?
What to do now

please help

Thanks in advance