My cpu ticks over at 300Mz when idling with screen on, see the attached. This is with all power saving options on. If yours is jammed at 1.4Ghz then either the kernel is corrupt (but you've reflashed) or the cpu has an internal issue.
Almost any app use will cause the cpu to jump to max frequency, so that doesn't mean anything.
All silicon is different, if yours is borderline specs then it may get warmer than another -provided the battery remains below 50 °C then no problem.
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