How to resolve graphic card problem?

First sorry because the bad English. I have a lenovo z575 laptop with a6-3400m quad core and 6720g2 (6520+6650) dual graphic. I always had problems with the graphic card or driver. Now in win 8.1 u1 when i start a game for the first time the driver crashes, so the game. The error message says: DirectX function "device->CreateTexture2D(&textDesc, desc.subResourceCount!= 0? Reinterpret_cast<const D3D11_SUBRESOURCE_DATA*>(desc.subResourceData) : 0, &texture->m_texture2d)" failed with DXGI_ERROR_DEVICE_REMOVED: Hardware device removed. GPU: "AMD Radeon HD 6520G", Driver:14.4 (14.10.1006-140417a-171098C). This error is usually caused by the graphic driver crashing: try install the latest drivers. Also, make sure you have a supported graphic card with at least 512MB.
I checked the drivers. Everything is all right. I reinstalled the system a week ago… But the problem is not new. I was getting i thing the same error but in another form, like BlueScreen, frozen system, etc. Somebody an idea? What should i try?