Hi Faragondk,
Are you saying you are hitting a memory leak problem? If so, I'm going to give this a shot but no guarantees I can fix anything.
What modern UI applications are you running? Please provide a list containing the exact name and author of the app.
And which version of Windows 8 are you running?
To get at the root of the problem, run the apps and, with the help of Task Manager, write down how much memory is consumed by each one. Then, wait 30-60 min, and again write down the amount of memory consumed by each one. The ones whose memory consumption is larger would be suspect.
Thanks,