Graphics have slowed down

[KirkyWirky]

Hello, just recently I have started to get lag and crashing on some games. It doesn't make sense because a few days ago I was able to run everything on the highest settings.
My specs are:

Core i7-2600 3.40 ghz
HD radeon 6850 1GB
8Gb Ram
650W power supply
6 Fans
Windows home premium 64bit

I don't think my graphics card is dying simply because it can still run lower end games. i did move it recently but i checked and everything seems secure. nothing is too hot temperature wise and everything except games is running fine. Although I can run low end games there was an fps drop in them.
Something weird that i noticed is that in the windows experience index the numbers have changed from:
Graphics: 7.6
Gaming Graphics: 7.6
to
Graphics: 5.5
Gaming Graphics: 6.0

I have already run defragment, updated drivers, updated windows and ran a scan. I even tried system recovery and i still had the same problem.

 

[KirkyWirky]

I have also had the same system for a bit over a year and never had any troubles with games

 

[popatim]

You moved it? From where and to where?

 

[smorizio]

check that the video cable connected to the gpu and not onboard video port if the mb has it.

 

[KirkyWirky]

i moved it from one house to another but i was holding it the whole time. The video cable is connected to the gpu