Flickering and coloring seem problematic

[pyzicslolito]

I bought a new computer of core i5 and with geforce gt 620 gpu support. I installed Windows 8.1 on it. However I can't play the game I used to play on Windows 7 anymore. I installed Windows 7 on a dual core processor with less ram than that of the current computer. Things were just fine. All the graphics and animation were smooth. They became laggy only when I opened and viewed many game windows at the same time. Now the game window on the new machine loses its borders, top menu bar and it always sticks to the top left corner of my monitor screen. ..I can't move it down. It is fixed up there. The game screen becomes like being laggy with an incorrect coloring scheme being used. Things occur with only one window opened. Sometimes I see dark blocks of pixels and the colors drawn aren't smooth. My monitor is of LG22EA53, Resolution is 1920 x1080. I also installed its driver on my machine.
Would you please offer me some advice or ideas as to why I run into something like that ?I am thinking better machines should offer better effects. . Thank you a lot.

 

[Enigman]

I think its the graphic card...not very spectacular ranking (174 out of 200)...http://community.futuremark.com/hardware/gpu/NVIDIA+GeForce+GT+620/review
Check the game section http://community.futuremark.com/hardware/gpu/NVIDIA+GeForce+GT+620/games
to see if your game is included and can be played in full settings. Otherwise lower the graphic settings of the game to make it work.
What's the RAM btw? And the Game?

 

[pyzicslolito]

I think its the graphic card...not very spectacular ranking (174 out of 200)...http://community.futuremark.com/hardware/gpu/NVIDIA+GeForce+GT+620/review
Check the game section http://community.futuremark.com/hardware/gpu/NVIDIA+GeForce+GT+620/games
to see if your game is included and can be played in full settings. Otherwise lower the graphic settings of the game to make it work.
What's the RAM btw? And the Game?

Thank you.
Here's the game I play http://boom.zing.vn. I have played only one game until now. I have a 4GB of RAM. I didn't know about the graphics card ranking.

 

[Enigman]

Make sure that you have installed DirectX http://support.microsoft.com/kb/179113 Most games require it to work well. And if all fails lower the resolution and settings to make it work.

 

[pyzicslolito]

Make sure that you have installed DirectX http://support.microsoft.com/kb/179113 Most games require it to work well. And if all fails lower the resolution and settings to make it work.

I have directX installed and no matter what resolution I change me screen to, the borderless game window is still stuck on the left top corner.