MPC 1000 screen blinks at startup

Hello

I just bought an used (very good condition as far as i can see) MPC 1000 loaded with JJ OS and 120 Gb hard drive and first thing i noticed is that the green screens blinks when the machine is starting up and loading the operating system and the hard drive is spinning to startup. Once the machine is already on, the screen light is very stable.
Does anyone has had this problem before?

Thanks!

Yes, I've noticed this, once in operation no problems, so no need to worry yet!