Good job on tweaking your Vcore. Manually tuning Vcore is always advisable rather than relying on Auto settings, which supplies considerably more voltage than necessary for stability. My 4770K requires 1.283 for stability at 4.7.
As long as your Vcore is under 1.300 and your Core temperatures are under 80C, then 4.7 will be fine. Since you decreased the Vcore, it would be interesting to know what your Core temperatures actually are with Prime95 v26.6 Small FFT's.
Although AIDA64 is fine for STABILITY testing, I'm not a big fan of AIDA64 for THERMAL testing for two reasons:
(1) There are too many test variables to allow for apples to apples comparisons here on the Forums, since almost no one bothers to be specific about what tests they've selected, which creates inconsistencies and much confusion concerning Core
(2) The only "Steady-State Workload" test which yields "Steady-State Core Temperatures" is the CPU test, only IF it's individually selected, and not run concurrently with any other test selections. Even so, AIDA64's CPU test runs well below TDP, and is therefore an insufficient "Thermal" test workload.
For the benefit of other Members, as well as Tom's ever-present silent readers in the background, what's so critical about "Steady-State"? Take a look:
Prime95 Small FFT's is the standard for CPU thermal testing, because it's a steady-state 100% workload. This is the test that Real Temp uses to test sensors. Version 26.6 is well suited to all Core i and Core 2 variants.
NOTE: (Do NOT run any versions of Prime95 later than 26.6. Here's why:
Core i 2nd, 3rd and 4th Generation CPU's have AVX (Advanced Vector Extension) instruction sets. Recent versions of Prime95, such as 28.5, run AVX code on the Floating Point Unit (FPU) math coprocessor, which produces extremely high temperatures. The FPU test in the stability testing utility AIDA64 shows similar results.
Prime95 v26.6 produces temperatures on 3rd and 4th Generation processors more consistent with 2nd Generation, which also have AVX instructions, but do not suffer from thermal extremes due to having a soldered Integrated Heat Spreader and a 35% larger Die).
Prime95's default test, Blend, is a cyclic workload for testing memory stability, and Large FFT's combines CPU and memory tests. As such, Blend and Large FFT's both have cyclic workloads which are unsuitable for CPU thermal testing.
Other stability tests such as Linpack and Intel Burn Test have cycles that peak at 110% workload, and are also unsuitable for CPU thermal testing. The software utility OCCT runs elements of Linpack and Prime95.
Shown above from left to right: Small FFT's, Blend, Linpack and Intel Burn Test.
Note the steady-state thermal signatures of Small FFT's, which allows accurate measurements of Core temperatures.
Shown above from left to right: Small FFT's, Intel Extreme Tuning Utility CPU Test, and AIDA64 CPU Test.
The "Charts" in SpeedFan span 13 minutes, and show how each test creates different thermal signatures. Intel Extreme Tuning Utility is also a cyclic workload. Although AIDA64's CPU test is steady-state, the workload is below Thermal Design Power (TDP), which is insufficient.
This is why I always recommend Prime95 v26.6 Small FFT's for THERMAL testing.