Hi Ramy. I'm Greg, an installation specialist and 9 year Windows MVP, here to help you.
Type Resource Monitor into Start Search. What Memory is reserved for hardware in Resource Monitor > Memory tab?
Also check in UEFI Setup for Graphics card settings to reapportion as necessary.
You can try other drivers, starting with the Lenovo Support Downloads web page for your exact model or Serial number from the sticker on the PC.
While there check also for newer chipset, BIOS, network, sound, USB3 and other drivers, comparing to the ones presently installed in Device Manager reached by right clicking the Start Menu.
if this doesn't give you the latest or ideal driver for what you need, compare it to the driver offered by the Intel driver update Utility here: http://www.intel.com/content/www/us/en/support/...
or the Nvidia Update utility here: http://www.nvidia.com/Download/Scan.aspx?lang=e...
or the AMD autodect utility here: http://support.amd.com/us/gpudownload/windows/P...
For Display issues one fix that is working is to Roll back or Uninstall the Driver on the Display Device > Driver tab, restart PC to reinstall driver.
You can also try older drivers in Device Manager > Display device > Driver tab > Update Driver > Browse > Let Me Pick.
Then you will know you've tried everything in addition to Windows Update drivers.
Also since the PC is new you have one year Support, Parts and Replacement Warranty I'd really use to get all issues either shaken out or a replacement that still has time to get all issues shaken out.
I hope this helps. Feel free to ask back any questions and let us know how it goes. I will keep working with you until it's resolved.
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