Hi again,
Success!? Well sort of. I've just received 3 "Chassis Assembly, Acoustic"
kits (part No: 70-31748-01) which consist of a disk mounting bracket with
some rubber bits. These were provided by DEC as part of our maintenance
agreements. Unfortunately, after fitting one of the kits it
didn't seem to make an awful amount of difference to the noise level, but
it did seem to lower the pitch somewhat. We intend to investigate the
disk mounting a bit further - I've got my eye on a big rubber mouse mat.
Our Alphas are all AlphaStation 200's - but Andrew Gallatin
<gallatin_at_isds.Duke.EDU> claimed to get better results with his 300's.
Many thanks to:
Don Newcomer <newcomer_at_dickinson.edu>
Dan Winger <winger_at_sewp.nasa.gov>
alan_at_nabeth.cxo.dec.com (Alan Rollow - Dr. File System's Home for Wayward
system PRIVILEGED account <root_at_borg.med.ecu.edu>
Oyanarte Portilho <portilho_at_fis.unb.br>
boris_at_gore.afep.cornell.edu
rnlott_at_milp.lsis.loral.com
Andrew Gallatin <gallatin_at_isds.Duke.EDU>
Ian
====== SUMMARY FOLLOWS =======
I asked:
>
> Hi
>
> This question has been raised before but I didn't see any
> summary.
>
> We have 3 Alpha's, all with RZ26L (1.0GB) disks which producde an
> extremely annoying scraping/rattling noise. Is there any way to reduce
> the noise from these disks ? I have seen hints to a noise
> reduction kit but no details...
>
> Thanks
>
> Ian
>
From: Don Newcomer <newcomer_at_dickinson.edu>
We noticed this in our 3300. DEC was called and every replacement disk
did the same thing. We lovingly refer to it as our popcorn popper. It's
a problem germane to that particular disk. If you're in a computer room
environment with air conditioning running, you don't notice it!
=========================================================================
From: Some wag from DEC:
Not speaking as a Digital employee (so please don't quote me), but the
internal joke is that the "L" on "RZ2xL" is for "loud". I'll be really
interested in hearing your summary. The RZ28L has the same noise.
=========================================================================
From: Dan Winger <winger_at_sewp.nasa.gov>
My RZ26 drive on my Alpha has the extremely annoying scraping/rattling
noise too. The only way I defeated the noise problem was to put the
CPU on some blocks underneath my desk in a corner with two half height
file cabinets on each side of it.
=========================================================================
From: alan_at_nabeth.cxo.dec.com (Alan Rollow - Dr. File System's Home for Wayward
Inodes.)
The HDA case of the RZ26L is also the disk mounting plate
in many systems. With a connection this direct, there is
little or no acoustic isolation between the disk and the
system case. So, the noise of every seek is passed onto
the system case. Other disks have used a mounting bracket
on the disk that was isolated from the HDA case.
In many systems, notably the DEC 3000 Model 300s, no extra
isolation is provided between disk and system case and so
you hear every seek.
When we were still making the RZ26L there was a test version
of the microcode that traded a little seek time to make the
seeks quieter, but I don't know what happened to the work
when Quantum bought that business. Whether anything can be
done to reduce the noise depends on the system enclosure
and how the disks are attached to the system case. The
DEC 3000 deskside systems (500/800/900) use rubber standoffs
that offer some isolation between the system frame and the
the disk mounting bracket. I don't know what other systems
use. The RZ26L I have in my Model 600 (desktop 3000) is
only a little more noisy than the RZ28. Much less so than
the disk in other systems that I've heard.
=========================================================================
From: system PRIVILEGED account <root_at_borg.med.ecu.edu>
We have the same problem. Let me know if you find a
solution
Cheers
Martyn
=========================================================================
From: Oyanarte Portilho <portilho_at_fis.unb.br>
We have got also a noisy internal disk drive in one of our alphas.
Maybe some grease on the bits would help ...
Oyanarte
=========================================================================
From: boris_at_gore.afep.cornell.edu
There was a thread on this subject. Open your Alpha and look at the disks.
The original RZ26's had metal posts that slide onto the frame and hold the disk
on. The newer ones have stiff rubber ones. I heard there's an upgrade kit.
The heads on the disk moves back and forth really fast, and effectively uses the
frame as a loudspeaker.
Cheap solution: stick a rubbery material in there somehow to stop metal to metal
contact.
=========================================================================
From: rnlott_at_milp.lsis.loral.com
dec has a new rev which corrects the noise problem on rz26l drives...hda is made
of different material.call dec fs to replace drives. Digital storage engineering
group is aware of the problem....and provide a new rev to quit drives.
robert lott
=========================================================================
From: Andrew Gallatin <gallatin_at_isds.Duke.EDU>
The part number is 70-31748-01 for a silencing mounting bracket that
fits in a 300 series alpha, and supposedly an AlphaStation 200 series
machine (I've only used them in 300s so far). They work wonders.
Received on Thu Aug 24 1995 - 15:48:44 NZST