For 7835 you should assume you bought the correct part no. for your region. You can check what part no. of toner you need at the Consumables Status by pressing the each row representing the toners. Below is a table with toners around the world:
think you for your replay,
I copy image and HDD from other working machine but this didn't resolve the problem;
i think that i have a hardware problem in controller card ,can you advice me where i can sheck the problem or if you have tips to resolve this problem of white screen and code 8?
thinks very much