APC Back-UPS 400 flashing light

About 3 days ago, I have noticed that the green light on my APC BAck-UPS 400 blinks like 5 times per second nonstop 90% of the time. I haven't changed anything in my computer, except I put a GF4 MX 440 in it about a week ago. The APC is over 4 years old, probably over 5...

I also have a no name brand 400w PSU that I've had hooked up for about 4-5 months.

Is this ok for my APC to do this? What should I do/ buy a better one? Do I stay away from APC CS series, because of all the recalls?

i would check the manual for any error or operational codes. do you have the manual still since you have had it for that long? i am sure the APC's site has something for you to reference.

dont think i have the manual, i guess i will try apc website, thanks

My guess would be that it's a light to indicate that the battery is charging. Your unit is a bit old, and the batteries may be wearing out, leading to a nearly constant need for charging, and a near-constant lighting of that green charge light.

I would still look for that manual, but I'd direct yoru research towards battery messages and replacement. -- Paul