SGI: Hardware

As very few of you will know (given by the lack of any response to my thread in the hinv forum - I guess Indigo2 hinvs aren't hot topics like they used to be), I've recently bought my most coveted SGI system - an Indigo2 IMPACT from the nice Mr Mapleson. And as expected for a high-end machine from the mid 90s, it's rather loud in comparison to modern machines.

So immediately, I decided to have a go at decreasing its decibel level quite dramatically. This was done in the knowledge that I live in the North of Scotland (so it's always cold), and the system only has SolidIMPACT (so no TRAM modules and only a single-slot card to worry about). The decision was to try and replace all three of the fans in it with modern, quiet fans - but ones which are still supposed to deliver a reasonable amount of airflow. Going by the excellent work of Megatron-UK on the specs of the original fans here , I was aiming for new fans that would still have 75-85% airflow of the originals, whilst being a more modern and quieter design.

Based on that, I bought two Zalman ZM-SF2 fans (rated airflow 43CFM compared with 55CFM for the original), and a StarTech FAN6X1TX3 for the CPU - 60mm x 10mm fans are bloody difficult to find, this one was bought on the basis that it had 17 year-old newer bearings and so should be quieter. The new fans are here (click for bigger pics!):



Next step was to open up the Indigo2, remove the 5 1/4" drive bay, SolidIMPACT card, EISA NIC and the riser. The system now looked like this, notice how nicely Ian cleaned it up before he sent it to me!:



Here is the riser with the old (but clean) Panaflo fan fitted to it:



The old Panaflo fan was removed, and the new fan was attached. Although the new fan has a 3-pin cable, it's straightforward to connect it to the 2-pin socket on the riser board with one of the pins of the plug floating in free air. Oh! and I also reversed the flow of the fan on my system - default was to blow air OUT at the front, and I don't like fans at the front and back both trying to extract air.

EDIT: Turns out it's a bit more difficult! The Indigo2 fan headers use a reversed polarity to the pins on a standard 3-pin fan. Basically, you need to use a screwdriver to pop the live and neutral pins out from the fan, then plug them in the other way around. Plug the fan onto the header and all will be well.

Anyway! Riser now looked like this:



Next was the CPU fan. This was a bit more difficult as the HUGE heatsink has recesses for the two screws to go into. The new fan didn't, so I had to "gently" remove two bits of plastic with a hacksaw so that it fitted flush into the heatsink. Not too difficult, and only took 5 minutes to do. Furthermore, the connector next to the heatsink is right next to a power transistor, so I had to physically trim the 3-pin plug down to the size of two pins (and remove the tacho cable). Here's the old and new fans, note the two missing bits of plastic on the corners of the new fan on the left, plus the trimmed connector.



With that done, it slots in nicely. Oh, and note that I subsequently noticed that the SGI fan has the live/neutral pins reversed, so I also had to pop the two connectors out the trimmed plug and swap them over so it'd work.



Next step was the PSU fan. Now the PSU contains lethal voltages, so I VERY carefully opened it up, then removed the input connector and removed the fan. The top board which springs out of the way is the danger one to avoid touching. Anyway, here it is with no fan:



...And again with the new fan fitted and the input connector replaced:

NOTE: Again, the PSU fan connector has a reversed polarity compared with a modern 3-pin fan. Again, the live/neutral connectors from the new fan need to be popped out and swapped over, before it's connected up (NOT shown in these pics!)



...And all screwed back together again:



Now, here's the Indigo2 with the PSU, riser, expansion cards and 5 1/4" drive bay all re-fitted:



Now at this point, I fired it up with the lid off to make sure that all the fans were working. They were, but the CPU fan - although quieter than before - was still noisy. As I said earlier, the StarTech fan was not designed to be a super quiet fan, just a new fan. So! Both Zalman fans came with a resistor expansion which drops the voltage, plus the heatsink for the R10000 is HUGE and the CPU doesn't dissipate a ridiculous amount of heat, so I added one of the resistors to the CPU fan like this, then tidied it away (second picture):




Last but not least, tried it again. The CPU fan still spins at a reasonable rate, produces a noticeable draft of air, but is MUCH quieter. So, feeling much happier I put the lid back on. And here's the final Indigo2 (sorry for the poor image quality, my phone flash ain't great!):



The results: The system is now VERY quiet. By far the loudest part is the 15k HDD inside. The fans are all spinning nicely and there's still a comfortable breeze coming from them. After running it for a while with the lid on, there's no ill effects, and the heat output from the system seems fine.

EDIT: The Zalman fans were spinning too slow originally as I'd connected them wrong, and the PSU heat level was too high. After fixing the polarity of the fan connectors and trying again, all is now well with noise and heat!

Note that I would think twice about this if I either had MaxIMPACT, or lived in a hot country. But for Scotland, the only audible noise my system now makes is the whine of the HDD. Might try it with a 10k drive to see if the noise/performance difference is worth it

Either way, turning an Indigo2 into a nice, quiet system is relatively straightforward and only cost me about £10 in new fans!

Edit2: Attached the images locally so they no longer rely on external hosting

I have never thought that the fan noise from my Indigo2s was loud or obnoxious. The old hard disks, on the other hand....
Those 50-pin disks are nearly 20 years old. The Fujitsu ones seemed to have quieter bearings, but what's really needed is a cable harness to attach recent LVD disks with fluid dynamic bearings.

Good work! and interesting pictures, too

oh nice one and a good reference for all indigo owners.
i have to agree to robespierre tho, the indigo2 is by far the most silent of all sgi machines i have. actually my pc is louder

Minor point I'd like to mention - the 36GB 15K drives I fit in Indigo2 are one of the quietest
drives I've come across (particular model of HP-branded Seagate, BF01885A34, Seagate
PN 9W7006-038), far better than the vast majority of 10Ks and way better than any original
disk for Indigo2 (it's almost as good as the Fujitsu MAS series). Only thing better in an Indigo2
is an SSD. If he can hear the disk now then indeed the new fans really must be quiet.

And yes, I totally clean every system before shipping.

Ian.

PS. Keep a careful watch on your R10K for a while. When I tested new fans on O2 CPU
modules, using ones with slighly lower air flow didn't work that well. In the end I found
a thicker fan with higher flow and less noise, whcih I fit to custom R12K/300 modules.

PPS. foetz, on Thursday I upgraded an Indy at a textile company with two OCZ Vertex4
64GB SSDs, R4K/200, max RAM. Since it has a Sony PSU, it now makes no noise at all .
Beats the Indigo2, hehe.

Nice write up Trippynet, thanks for taking the time to create and share your work.

If I had one minor suggestion to offer, it would be to attach the photos to your post.

There have been a number of instances in the past where for one reason or another the off-site photo links have gone dead in similar posts, leaving those posts incomplete.

If you'd consider attaching the photos, just scale the photos for attachment to a reasonable size for on-line viewing, (I usually set the longer aspect to 1000px), and the forum interface will automatically create a smaller thumbnail for display in the article. The reader can view thew larger version by clicking the thumbnail.

In either case, thanks again for sharing.

mapesdhs wrote: PPS. foetz, on Thursday I upgraded an Indy at a textile company with two OCZ Vertex4
64GB SSDs, R4K/200, max RAM. Since it has a Sony PSU, it now makes no noise at all .
Beats the Indigo2, hehe.

haha okay, i guess there's always an extreme example

I also replaced their dying external floppy and DDS2 with another 64GB Vertex4,
stored in the case which used to hold the DAT. It's cut the time for their full
backup from 30 mins to 5 mins, and the guy loves the random access nature &
flexibility of the SSD vs. how one must deal with DAT. Textile patterns are a
perfect fit for SSDs - lots of very small files. Their whole archive is currently only
75MB, but it has more than 22000 files.

Sorry, I digress... Indigo2 roolz!

Ian.

mapesdhs wrote: I also replaced their dying external floppy and DDS2 with anotehr 64GB Vertex4,
stored in the case which used to hold the DAT. It's the the time for their full
backup from 30 mins to 5 mins, and the guy loves the random access nature &
flexibility of the SSD vs. how one must deal with DAT. Textile patterns are a
perfect fit for SSDs - lots of very small files. Their whole archive is currently only
75MB, but it has more than 22000 files.

This is fascinating to me, do they have a website? Are they just doing this just for file storage or is there some industrial control that they're also running on the Indy? For example arahne?

mapesdhs wrote: Sorry, I digress... Indigo2 roolz!

True dat!

erm, how do you get an ssd in an indy?
converter or something?

vishnu wrote: This is fascinating to me, do they have a website? Are they just doing this just for file storage or is there some industrial control that they're also running on the Indy?...

No site that refers to the Indy. The Indy is called a Stoll/SIRIX system; they were sold without any SGI markings. It's used to
control more than a dozen large knitting machines, each between 2m and 4m long, big warehouse style factory. Scarves, gloves,
jumpers, hats, etc. The Indy connects to each knitting machine via a Selan, a sort of network box connected to the serial port.

Ian.

foetz wrote: erm, how do you get an ssd in an indy?
converter or something?

Acard ARS-2160 SCSI/SATA bridge box (SCA version) + direct low-profile 50/80pin adapter.
The bridge box has the same 3.5" 1/3rd height form factor as a normal HDD. Here's a pic of the
system with the two internal units fitted:



So far I've tested the folllowing SSDs & confirmed they will work ok in Indy/Indigo2/Fuel/Tezro, so
they should be ok with all other SGIs: OCZ Vertex2E/3/4, Vector, Samsung 830 & Samsung 840 Pro.
Hence, one could have an Indigo2 with a 512GB 840 Pro.

For reference, the Acard bridge boxes cost about 155 to 195 UKP each depending on the source.

I had recommended the company use 128GB 840 Pro SSDs, but ended up going with 64GB Vertex4s
to reduce the cost a bit.

Ian.

Thanks for the feedback! I must admit that the Indigo2 was probably quite comparable with PCs of the 90s era as well when it first cam along, however I have been a bit of a sucker for a quiet system over the last handful of years (although not to ridiculous levels mind you). My PC has 2 12cm fans from QuietPC and a gigantic quiet CPU cooler on, hence it's whisper quiet. My O2 used to have a noisy fan, but this was replaced with the Nocturna one recommended on Neko. Result is that it's virtually silent when turned on, and only makes a bit of noise once the two HDDs fire up into life. Heat output from it is absolutely fine.Then again, it only has an R5000 in it.

As for the Indigo2, the heat output from the SolidIMPACT card is absolutely fine at the moment (only lukewarm air coming out the vents at the back, even if the heatsink on the card itself is quite warm). The CPU heatsink is warm but not hot to the touch, and can be easily touched for a prolonged period after an hour of use without any problems/burning skin. Only bit I find slightly concerning is that the PSU is definitely kicking out some seriously warm air at the moment, probably about 35-40 degrees or so. QuietPC do another Zalman fan with a higher air throughput (it's about 56CFM compared with 43CFM for the current fan) and it's only about £4, so I might have a go at fitting a slightly higher-rated fan to the PSU to try and help here. Like I say, it's all about trying to balance noise with making sure that my Indigo2 still receives adequate cooling.

Oh, and I can confirm that the HDD in the Indigo2 is not exactly noisy as such - certainly not when compared to the old 50pin HDDs I used to run in my Indy! It's a 36GB 15K 80pin drive being run through an 80->50 adaptor (the drive Ian mentions above). However, it is definitely the noisiest part of the system, but even then it's still just a fairly quiet hum in the background. To be honest, I'll probably keep it as it is. Either way, it's not much louder than my PC, and can happily sit there next to my desk without the noise being distracting now - which was the whole point!

Edit: I've decided that I won't be going down the SSD route. It's just not worth it IMO given the costs involved when the system only has a 10MB SCSI connection on it. After all, I'm not *that* bothered about the noise! Now in a Fuel, Tezro or even an Octane with the right SCSI card, it's a different story...

thanks for the details and pic ian. quite tempting but only with another scsi controller as Trippynet mentioned already there:

Trippynet wrote: the system only has a 10MB SCSI

unfortunately a ciprico is quite rare and still afaik only works as option disk i.e. not bootable.

Trippynet wrote: Thanks for the feedback! I must admit that the Indigo2 was probably quite comparable with PCs of the 90s era ...

Hang on a sec, Trip. Just one point. Windows 95, bless its little DOS heart, came out at the end of 1995. The Pentium Pro (180 and 200 mhz) came out some time around then. Around 1998 I had a neighbor with a purple Indigo2 which made my hot-to-trot peecee look like that retarded kid on the Special Olympics poster. The Indigo2 throughout the 90's would kick peecee ass both in hardware and software, from here to Uranus

It wasn't until the mid-2000's that a peecee could honestly claim to be somewhat equal to an Indigo2. Around 2000 I dragged a lowly Indy to China, where it was faster and better than any of the peecee's that company had.

Let us not disparage our own proud roots

Trippynet wrote: Oh! and I also reversed the flow of the fan on my system - default was to blow air OUT at the front, and I don't like fans at the front and back both trying to extract air

Not sure, but I maybe it was originally back to front because of the way the ASICs are placed on the graphics boards. Especially with IMPACT graphics, all the big ASICs, TRAMS etc are located near the front of the machine. So with air flow back to front you don't pull the hot air over the rest of the PCB, but it goes straight out instead.

I've got Brocade 5000 FC switches. They use ~ 50W (which isn't much for a 32 port 4Gb FC switch), and nearly all of it must be consumed by the SFPs. Which are at the front, obviously. So the airflow is back to front. If the hot air were guided out the back, you would need additional airflow to keep the temperature of the internals within bounds.

Oh, and I used to have a cat who loved to sleep in front of my MaxIMPACT 10K Indigo2. Didn't care about the noise, loved the hot air flow

Hang on a sec, Trip. Just one point. Windows 95, bless its little DOS heart, came out at the end of 1995. The Pentium Pro (180 and 200 mhz) came out some time around then. Around 1998 I had a neighbor with a purple Indigo2 which made my hot-to-trot peecee look like that retarded kid on the Special Olympics poster. The Indigo2 throughout the 90's would kick peecee ass both in hardware and software, from here to Uranus

Err... we're talking about noise output here, not computing performance. I'm well aware that an Indigo2 IMACT will trounce a mid 90s PC when it comes to performance

Trippynet wrote:

Hang on a sec, Trip. Just one point. Windows 95, bless its little DOS heart, came out at the end of 1995. The Pentium Pro (180 and 200 mhz) came out some time around then. Around 1998 I had a neighbor with a purple Indigo2 which made my hot-to-trot peecee look like that retarded kid on the Special Olympics poster. The Indigo2 throughout the 90's would kick peecee ass both in hardware and software, from here to Uranus

Err... we're talking about noise output here, not computing performance. I'm well aware that an Indigo2 IMACT will trounce a mid 90s PC when it comes to performance

Yeah, I did react to that too, but thought that you must have talked about fans and noise.

OK, an update to this:

First of all, I was becoming increasingly concerned about the heat of the PSU, so I went ahead and bought a new fan with a higher CFM rating for the PSU. Fitted it, powered up the system, and the fan refused to spin. So as it's a 3pin connector (2 pin plug in the PSU), I opened it up again and moved it across by one pin. Still refused to spin!

This time, I did a chunk more digging around and found that ALL THREE of the SGI fan connectors have their polarity reversed from those on a 3-pin connector. Manually popped the pins out, reversed the live/neutral, connected all back up and the new fan roared into life (almost as loud as the original). Of course at this point, I was admittedly a bit confused as to why the Zalman fans in post 1 were working at all as these were connected with the original pinouts.

Long story short, it turns out that I had them connected with the live and tacho pins, but not the neutral. Amazingly, they still span when connected like this, but after swapping the pins around and connecting them up again, they spin MUCH faster and yet only make a fairly quiet hum.

So to cap it all, I now have the white Zalman fans fitted again in the PSU and expansion tray, but with the live and neutral pins connected correctly. Air output from them is about twice what it was before and the PSU is now emitting heat which I consider to be perfectly acceptable. The Indigo2 does make a noticeable noise now, but it's much quieter than it was with the stock fans.

I'll update the first post with this new info!

Another update:

Although my Indigo2 was quietened to the level that I could happily have it humming away on my desk for a while, it was still making a fair bit of noise, and I eventually traced this to the hard drives. Not the physical drives themselves, but the fact that they seem to be resonating with the case and producing quite an amplified hum as a result.

So, I chopped 8 little squares off an old and very thin mousemat, punched a hole in each of them, then I removed and re-mounted both of the HDDs so that they're sitting on these new rubber "washers".

Powered it back up, and no more resonating hum, and the system is noticeably quieter as a result. Well worth doing!