We currently have a number of HP Z800 workstations that perform very well for the purpose they were selected to perform. When we first purchased them, we were impressed by the quietness of these machines but over time, however, we feel the fan noise from these machines has been increasing to the point that it is now intolerable.
We have done all the basics: cleaning them thoroughly with vacuum cleaners and blowers, checking the cases are correctly sealed,operating them with most PCI devices removed and checking the fan speeds. They are loud even at the lowest speed, the BIOS shows them running at 1400 - 1800 rpm when idle. We did some tests removing individual fans temporarily and found that pretty much 95% of the noise comes from the case fan at the rear (534878-001) and the memory fans (534879-001)
We tried replacing these parts with "new" fan kits ordered from a HP authorized distributor. When the new fan kits arrived, the sound levels didn't change. We looked closely at the new fans and found they were actually manufactured earlier than the fans we took out of the system (2009!). The vendor, Delta Electronics, puts a date code on them. I'm guessing the lubricant quality deteriorates if they spend 8 - 9 years on the shelf.
What are the next steps? Is there any way to get freshly manufactured fans for Z800?
Are any of the newer Z series workstations significantly more quiet? Will a modern Z440 be as fast or faster than a 7 year old Z800 with a single CPU?
Are there any workstations from other vendors, e.g. Lenovo, Fujitsu or Dell that are considered to be more quiet than the Z series from HP?