Battery drain issues after installing external memory card !!

[Agera One]

Hi guys, it's been long since I used THF. I have a problem.

I bought a new Samsung Galaxy S3 Neo GT-I9300I and updated to Android v4.4.4. These were the things I noticed at first:
1) I charge my battery to 100 (battery fully charged) right before sleep (11 PM) and i have 99/98% remaining in morning (without wifi/mobile data/ background apps) at 7 AM.
2) Then after reaching office with 95%, I'll use wifi/mobile data (2G) for total 1 hour and in the evening I will have around 80-85% in the evening at 7 PM. (THESE WERE NOTICED FOR SEVERAL DAYS)

After two weeks, I got this external memory card from Amazon.in.

After installing SD card, I ran A1 SD bench in my phone (with and without data in the external memory) and it showed awesome results.

I don't have any data on my SD card now. When I go to sleep with 100% battery under the same condition of no wifi/mobile data/ background apps, the charge gets to 88/87% in the morning and the same office use gets me to 60% at 8PM in the evening. (THESE WERE ALSO NOTICED FOR SEVERAL DAYS)

I'm draining 10-12% faster than before.

so, Is the sd card the problem or something I should tweak my mobile settings?
Can factory reset make a difference?

Thanks in advance.

 

[GeRgY]

Factory reset works for every old phone but you should try another way.
Get this card off and FORMAT it with computer. Then watch over your APPS and remember that only APPS can drain battery that faster.
If some of your applications work on stand by mode ( background mode ) your phone can lose battery more faster than 10-12%. So...
1) Save your data (pics, videos and etc.) on a computer
2) Format this phone clear with FULL factory reset and then insert the formated SD card.
3) Remember that this phone is not high end smartphone and some apps uses more power to works (like the game Hearthstone on my HTC drains 10% per 15-20 min )
Final words: Just try to make you phone clean and don't blast him with alot of trash programs. When you factory reset this phone install "Clean Master" from app store and this app will become your problem fixer
I am not 100% .. i am 1000% that when you make this steps you wont get any problems with this S3