Has your PC been overheating or running slower than normal. If you have already optimized the hard drive, there is one more operation you may also want to perform. This will require opening the case, so if you are uncomfortable doing that you should enlist the services of a qualified technician (like me). Most desktop PCs have multiple fans bringing in fresh air and exhausting the hot air in an effort to maintain the performance of the components. However unless your PC is located in a NASA clean room, dust, pet hair and other particles will find a way into the case and decrease the PC's cooling efficiency. The best way to remove this dusty build up is with an electric leaf blower (it is recommended that this is done outside in a well ventilated area for obvious reasons.). Most if not all the dust will be removed. Any remaining particles can be wiped off with a cloth or Q-tip (for the difficult to reach places.) I perform this service on every PC I diagnose, repair, or upgrade.