Laptop Screen Suddenly Flickers

Hello, I have a Dell Inspiron 3421 Core i3 (Ubuntu) 4GB ram, Windows 8.1 pro installed with Intel HD graphics 4000.

Laptop screen sometime flickers but when i restart the laptop it goes to normal condition and works fine for almost 2-3 day after that i get such issue again i don't know it's an hardware issue or an software driver issue.

I Have tested Graphic through Dell hardware test everything worked fine my laptop passed that test.I have check the dell auto driver update program and update all the drivers except Bios because i thought it may go wrong and something else get happens and i left that update as it is.

Few of my friend discussed with me and told me that this issue may occurs due to Ubuntu, Because Ubuntu system does not detects and install windows drivers by there own so there is problem with your driver not any hardware problem , If it was hardware problem then it would not go fine after restarting the system, Look for the drivers manually by your own.

Please advice me what should i do?I again mention it that this problem occurs suddenly not on a specific point.

Earlier i had windows 7 when 1st time problem occurs at every startup on Windows 7 theme transparency enable i get black and white weird screen and i just uncheck few options of Intel HD 4000 graphics as I do remember it was like display refresh rate and 1 an other option i unchecked i don't remember exact .When i have done that It worked fine on starting but it sometime occurs exact same as it's happening on windows 8.1 now but currently i have not unchecked or changed anything from intel graphic HD 4000 after installing windows 8.1.

waiting for your help