Sims 3 Screen Flickering

@berczya  Thanks for including the dxdiag; it's very helpful.  I'm not sure which expansion packs you're running, but your integrated graphics card would probably have a lot of trouble with Pets, Seasons, ITF, and IP.  These packs really do require a strong dedicated card to run properly.  (Your other specs are great.)  Your card's performance would also likely vary depending on the in-game weather, the presence of pets, and which world you're playing in.

It's possible, although not likely, that something in your game folder is causing problems.  You can test this by pulling the entire folder out of Documents and launching the game again, which will spawn a clean folder.  Start a new save in this folder and take a look around.  Try a couple of well-made EA worlds, like Sunset Valley or Riverview.  If the graphics are better, try adding an existing save to the new folder and test that too.  If this helps, you can just move the rest of your saves and other content into the new folder.

If Origin happens to have messed with your game, you can run a Repair Game command by clicking on the TS3 icon in your Origin library.

I do think, though, that your graphics card is the most likely culprit.  You might get better results by turning down your graphics options, especially water and high-detail lots; I have a fairly strong card, and I keep these at "mirror only" and 2, respectively.  You could also switch between fullscreen and windowed mode to see if one is better than the other.  If windowed mode works but the UI is too small, you might look into Windowed Borderless Gaming.

Integrated cards can't usually throw high frame rates like dedicated ones, so tools that limit in-game fps aren't normally recommended.  But you might try one like RivaTuner Statistics Server (free download) to see if it can get rid of the flickering.  (It does need to be running while you play in order for it to work.)  Here's a screenshot of the settings you'd want:

https://forums.thesims.com/en_US/discussion/comment/16227429#Comment_16227429

Ultimately, though, there might not be a lot you can do to play TS3 the way you want.  Unfortunately, your card is never going to be able to keep up with TS3's demands, and you might not be able to improve much on its performance.

@berczya  The video system does not meet the minimum requirement for this game. Dxdiag reports 112 Mb of dedicated memory and the minimum requirement is 128Mb dedicated video memory. A solution would be to install a video card in the empty slot in the mother board. My will probably have to upgrade the 180 W power supply. I also recommend connecting to the monitor with a HDMI cable as VGA is very dated.