721 drive noise

[marshalk]

My 721 has been getting increasingly noisy for the past few weeks. At first I thought it was just the fan but it began to sound more and more like the drive. While the 721 has always been loud, louder than something like home entertainment equipement should be, it has been tolerable. After getting enough complaints about being able to hear it from the dining room I decided to jump in and perform surgery. I removed it from my system and opened it up. While plugged in I could pull the connector on the fan beneath the drive for a second to listen to the sound. The fan itself is fairly quiet. The sound was coming more from the drive itself. This next step is not for the faint of heart....I pulled the power connector from the drive. Clearly the source of the noise. It is a loud hard drive. Can we swap out the drive? Is there enough of an OS in ROM that it could boot up and download current software and generally deal with a new drive?

Does anyone else observe anything like this? Could be the drive is going out but I have had computer drives sound like this and live for years.

[John_ZD]

The harddrive runs hot in the 721 which will cause the bearings to get loud overtime. The only way to keep the drive quiet is to force the fan to always run. The fan won't turn on normally until the temp sensor inside the 721 reaches 122 degrees - the harddrive could easily be 20 degrees warmer then that...

The same harddrive in most computers would run quite a bit cooler because the airflow provided by the power supply fan.
I know the 721 can limp along without the harddrive, no idea if it can deal with a totally blank drive though.

[marshalk]

Are you suggesting that if I cooled it down more it would be quiter or that the bearings are a bit worn now and it will be loud permanently? If better cooling would help I could deal with that a bit with a slot fan or bigger fan beneath the drive.

[John_ZD]

Adding a fan now will likely quiet the harddrive down a little but its doubtful it'll ever run as quiet as it would have been if kept cool its entire life.

FYI my 721 internal temp is currently 119.7 degrees.

[James_F]

DirecTiVo runs at 133 (45c). It used to run at 125 but I raised the unit up and let some air flow all around the unit. I used some of those 35mm film caps (the grey ones).

[marshalk]

I think I will give that dynamat stuff a look and replace the existing fan with a slightly larger (and quiter) one from pc power and cooling. I have used their fans in PCs and they work well while reducing noise. Perhaps the dynamat material will deaden the noise a bit. Theoretically the increased fan will cool more and compensate for any thermal insulating that the sound insulation does.