I recently built a SCSI RAID server for a law firm. The machine was spec'd with six IBM 10,000 rpm drives to be installed in an Aopen HX08 full tower - with RAID5 on all but one used for the O/S.
The machine had been up and running trouble free for a week and I stopped by to check on it. Sliding off the side cover I realized it was quite a bit hotter inside the case - it's running dual PIII 866eb's but that wasn't the source of the heat, it was the drives! I touched the backs where I could reach but it didn't seem too bad - so I pulled out one of the mounting screws to try and get an idea of just how hot they were and couldn't hold it between my fingers it was so hot! I would estimate the internal temperature of the drives was 80c+ but I didn't have a way to accurately measure it.
The HX08 is an average case, and the removable drive cage on top would probably be OK for an IDE raid setup but these drives were smokin! Even with 2 80cfm fans in the back, the drives were just to close together to get decent airflow.
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