I am considering purchasing a tuner card for watching HD on my computer. The minimum requirements for an HD tuner is a Pentium 4 processor running at 2.2 GHz. The processor on my desktop computer is a Pentium 4 2 GHz. I have read that a faster video card may reduce the load on the processor for this type of application, so I may not need to upgrade my processor in that case. Is this true?