I've just bought my rpi b+. Power supply for raspberry is 4.94V (which is in appropriate 4.75-5.25Vrange).
Raspberry pi working good, but there is one possible trouble. I don't know why, but power led (and rainbow square at top right of display) randomly blinking (approximate 1 blink for 30 seconds-1 minute, there is no direct dependence). Does this behaviour of raspberry pi is normal? What are possible causes for this issue?
UPD: I've noticed short blinks are usually coming on specific actions, like opening a new tab in the browser