SGI: Hardware

In my Make-The-Fuel-Quieter project of a while back I not only replaced the fans and got some good results, but I also used some of the silicone washers I got with the fans to dampen parts of the casing. In particular, i shoved washers down one side of each vrpo fan to stop them from rattling in their blue shroud.



Which got me thinking: redbox stil has some annoying sound characteristics. Perhaps there's more I can do.

So, this morning I opened it up and did some prodding and poking and discovered that the system drive mounted in the 3.5" middle drive bays with the blue SGI-supplied drive rails was vibrating the 5.25" drive bays above it, resulting in an audible drone. Prodding/poking/dampening the bottom drive bay fan also resulted in a reduction of drone.



Armed with the new prodding data, I hopped out to Maplins and got a packet of rubber fan mounts.



Cutting off some of the fan mount rubber allowed me to remount the middle drive bay fan using the original (long-ish) screws with the cut-down rubber mounts on the diagonal. (4 fan mount holes, two screws, two rubber mounts). The result is a significant reduction in resonance drone eminating from that fan and the surrounding case metal.

I then removed the system drive from the middle drive bays and booted redbox - obviously the resonance drone from the top 5.25" bays disappeared completely. However, when placed in the bottom bays the drive produced a new resonance, but padding the bottom bay with silicone washers has significantly reduced the new resonance.

Top tip: make a long masking tape inside out sticky thing first, then place the washers on the sticky thing and cut between each washer to reduce clumsy finger tape stickage when trying to make perfect 7mm inside out masking tape loops.



The drive just sits in the bay, no screws or fixings are used.



Given that I plan to re-install IRIX, I proceeded to test each of the SCSI/SCA drives I have to find the quietest one. It seems that my 147Gb 15k drives all produce a piercing high-pitched whine. Some of the 10k units of various sizes just made a lot of noise in general. I've settled on a 36Gb 10k Fujitsu unit re-badged by HP. It too has a whine, albeit at a softer volume and most importantly at a lower and more sufferable pitch. I do not have enough drives at hand to offer recommendation for a model/make/type, but it seems fair to say that 15k units will always emit a very high pitched whine.



Finally, padding the ends of the case crossbar (what a POS the Fuel case is) with some of the silicone washers seem to have removed some noise/vibration too.

But at this point I might be starting to hear things

Nice work Which fans did you replace and what did you replace them with?

Pontus wrote: Nice work Which fans did you replace and what did you replace them with?

Specs and story at the bottom of this old thread:

viewtopic.php?f=3&t=16725732

Does the Scythe Kama Flow in your PSU require suspending environmental monitoring?

GL1zdA wrote: Does the Scythe Kama Flow in your PSU require suspending environmental monitoring?

'require' - no it didn't. It worked just fine. Past tense. A couple of months after replacing the original fan, that PSU failed. I lack the hardware skills and tools to do any forensics so it's hard to say if it was the fan or if it just failed from 'failure'. So, I blamed myself for being adventurous, got a new PSU and to be on the safe side didn't replace the fan again. Since then redbox has seen some resonably long working hours without any issues.

But now I have a spare PSU on the shelf and maybe it's time to be brave again. If the PSU dies again we can be rpetty sure it was the fan replacement.

In fact, if I still have a spare quiet fan lying about that's exactly what I'm going to do... watch this space.

I replaced my broken Fuel PSU with an ATX PSU. It works fine, except the fan. The L1 environmental controller needs to get a "correct" tachometer reading from the fan. My replacement PSU didn't produce the proper signal (I don't remember the exact details)

What I did was to take the original PSU fan and strap it on the outside of the box, just running power and tachometer cables to it. So it doesn't actually cool the computer, but it keeps L1 happy. (The new ATX PSU of course has a fan to keep things cool).

I did try with a Noctua fan, but L1 didn't get any reading from that.

I would like to find a nice 12cm fan that fits the PSU and produces a signal that satisfies L1. When time comes I'll try a fan from Scythe.

Pontus wrote: What I did was to take the original PSU fan and strap it on the outside of the box, just running power and tachometer cables to it. So it doesn't actually cool the computer, but it keeps L1 happy.

I ran the Fool for years with the environment monitoring turned off. Sounds bad but the Octane doesn't have it, so what the heck.

I did the same. Replaced almost all the fans and then disabled environmental monitoring.

One quick note jimmer, some of the quietest hard drives I have are actually 15k ones. They do exist, so don't just assume that a 15k one will make an annoying noise. Of course, I've also come across my fair share of dreadfully noisy drives - including quite a few awful 10k drives.

I'm certain that it'll be fine without environment monitoring. I just want the satisfaction of fixing something broken.