Noted and thanks again for your help 
Best,
Updates
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I reinstalled Windows 7 and ran the Windows assessment, the score for the processor was different from the original BIOS which was 6.3. So I wonder if this has something to do with the modded BIOS (the machine from which the modded BIOS was built has an i7 processor, while mine is an i5)
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The machine freezes a lot both in BIOS and Windows. I read that if the BIOS is loaded from another machine, the ME region is mismatched hence causing all the glitches.
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I wonder if the BIOS update utility originally from VAIO BIOS Update Utility.zip (5.5 MB) will get the machine back to previous state or the modded BIOS has tampered other parts of the firmware.
Please advise on this 
As far as I remember you did just flash the bios region, ME is untouched, but it might be corrupted anyway.
You did flash a complete bios region including ‘foreign’ nvram settings.
A stock update will mostly not overwrite ME and normally not overwrite NVRAM.
You could buy a CH341 programmer, dump the complete firmware, refresh the ME region and empty NVRam. But I don’t think that all this will help you much.
I don’t understand the performance thing- was it 3.5 versus 6.3 with identical hardware? Checked temperatures?
I don’t understand the performance thing- was it 3.5 versus 6.3 with identical hardware? Checked temperatures?
Yes sir. The hardware remain unchanged, I just repasted the cpu and gpu so temperature is not a problem here.
From what you said, I suspect the only remaining thing of my original bios is the DMI that you helped reload. Everything else in the bios now is the foreign stuff that I flashed 
If so, it makes sense that the i5 CPU is underperformed compared to the i7 of the foreign bios.
For the ME, is there any way to check if it is corrupted?
Can you also let me know what is inside the ROM extracted using Universal BIOS Backup Tool?