If you're noticing that the 'ink' isn't staying on the printed page like it should it may not be a problem with the ink/toner but rather the fuser. This helps the toner to adhere the paper. If it's old or worn out it NEEDS to be replaced, and for the HP LJ P4015 installation is as easy as pie. There are You Tube videos available that easily show you how. I hope you find this information encouraging and helpful.