I think it is true. 7200 HD's generate more heat and consume more power, which could cause trouble to a sat receiver. They are meant usually for desktop pc's and are avoided even in laptops (until recently, at least). Normal usage in a sat receiver, does not require their extra speed. I have a Seagate 1TB HD which works great (5800, or 5900 RPM, don't remember, not 5400 though). So, try to find a 'green', low-consumption HD. Also, I'm not sure if there's a maximum TB limit.