SGI Indigo |
 |
Converted
to a PC!|
The Thoroughbred of its Day Click on images for larger popup Original Silicon Graphics IRIS Indigo.
RRP: £12,000 on eBay £100. Got a second one for
£10 P&P! 33Mhz 32bit CPU, 192Mb memory, 2x 2Gb SCSI HDD, Entry level graphics module. |
 |
This is how computers should be built; Back plane, CPU Module, Graphics module, HDD's and PSU all just slotting in. You can dismantle the whole machine apart without removing a single screw in under 30 seconds! |
 |
Processor module - you can change this for different configurations. I'm not sure that this meant you had to reinstall the IRIX OS either, perhaps install some overlays. No cooling fins - those where the days! |
 |
| Slot in Graphics module |  |
| The Graphics Module featuring spare sockets for more processors and (I think) 32Mb of memory - Believe me, in 1991 this had the performance of a GeForce 2 or TNT2 Ultra which was mind melting at the time. |  |
| Back plane connections. |  |
| Removal of hard drives again is easy as anything; Flick the lever and thats it! |  |
| Checking a PCI network card reveals how close the SGI is to PC design. |
 |
Removing the Skin This is, contrary to another popular SGI Indigo mod site, *VERY* simple! Remove the one screw. |
 |
| Press these two tabs in |  |
| et voila! |  |
| The naked Indigo - Oooh! |
 |
| The PSU just slides out |  |
| It oddly too has the system speaker attached. |  |
| The PSU has input and output sockets plus a hardware switch. I wanted to use as much original stuff as possible so these stay no matter what. |  |
| Almost there. The back plane clips in. |  |
| And thats it, the heart of the computer; A Cray designed system bus - every home should have one! |
 |
| Now the hard bits... |  |
| I shall not name who I bought this machine off but it had been sprayed with wheel silver paint to hide the considerable rust. Grrr! |  |
| The PSU - Designed by ITT (Yes, remember them!) a neat little unit. |
 |
 |
|
The Donor System Take one Duron 1.3Ghz PC with 512Mb and TNT2 Ultra graphics card (apt) |
 |
| The PC's layout |  |
| Well, the motherboard fits - not too late to put everything back, do check these things! |  |
| Hmmm... Some system skin remodelling will be needed. I tried to avoid this as much as possible. |  |
| As luck would have it the PC case had a riveted in strip of metal for mounting the blanking plates etc. |
 |
| Moments later - These rivets are only aluminum so even my £8 drill could remove them toot suite. |  |
| Returning the PC to its constituent parts - the point of no return! |  |
| Recently I had a Windows 2000 system come to me where the owner had been playing with Control Panel |
 |
| The backing plate fits! This really was the smug bit of the day :o) |  |
| It was such a snug fit that it almost denied the use of any fixing. |  |
The Power Supply Unit (PSU) This really was a different story! |
 |
| Open the case and remove any trace of ITT PSU. Also try and remove any studs from the case metal work unless they are explicitly useful. All PSUs are different inside. Here I have just stuffed the PC PSU guts to see if the lid will fit... |
 |
| ...It does. Second smug moment, time for more coffee! |  |
| Rewire sockets. |  |
| Add speaker cable to the speaker |  |
| Even the speaker has SGI printed on the back! But what do you expect from a $X0k machine that has Made in Switzerland printed on the back? |  |
| Here's a neat trick, I have an old Pentium Pro 200Mhz machine in the garage I use as a test bed. I tried firing it up with the SGI/PC PSU first. Hearing those POST beeps was sweet music even though it worked first time. |  |
| The SGI chassis and skin with the new PSU - completely original except for the wiring which the SGI never had. The SGI Reset button is now the power button. So in operation you open the front flap and use you little finger to push the 'secret' power button. |  |
|
|
 |
| One thing I sadly don't appear to have a photo of is how I mounted the motherboard. Basically I cut out the essential mounting section of the PC chassis i.e. Where the motherboard required ferrules and carefully marked where the edge of this lay when the motherboard was seated on it. I then marked the holes on the side of the SGI chassis, drilled them and put the PC plate outside the SGI chassis (once again, hidden between SGI chassis and skin) so that only the ferrules protrude on the inside. Fiddley but worth doing! |  |
| The motherboard mounted. Dusty case... |  |
| I have had loads of computer kit from ex-corporate dealers. Generally it comes in with laser printer carbon, sweat and finger grease engrained into the surfaces plus glue from stickers. Its pretty simple to remove; White Spirit, then Metholated Spirit to remove the stubborn glue and White Spirit grease, then Mr.Muscle which eats protein and fat molecules, then finally washing up liquid which cleans off Mr.Muscle residue. This also leaves the bath lovely and clean too! |  |
| End of Day 1 and its looking good! |
 |
| Hmmm... Door doesn't shut Tomorrow.. |  |
Day Two This weird futuristic plane flew over during the second morning - in a purple sky! A good omen! |
 |
| SGI used these screws for the PSU housing... |  |
| ...And whats this, purple security paint too! |
 |
| Nadgers, I knew this was going too well. |  |
| The PSU wouldn't go fully back in place |  |
| This was caused by standard PC screws holding cards in intercluding with the PSU case transit |  |
| The solution was to use countersunk miniature bolts. The blanking plates had to have the bottom tab cut off anyway as else it would have protruded from the side of the case. |  |
There, job done! Note: UltraSCSI. An SGI without it? Not while theres breath in my body! |
 |
| >Shudder!< My beautiful creation... |  |
|
It lives! Duronimo started first time and stayed working for a while. The only problems I've had are that I had to build a second PSU (!) as there was not enough cooling for the first one which fried luckily not taking the motherboard and everything else with it. I have since added a case fan and have not had this problem since. The case fan nicely fits in with the venting at the bottom of the door. |
 |
|
Updates The PSU died because I'm an animator and I left it on for a long period rendering animation which obviously uses 100% CPU time, all the time. Cooling became an issue - The orignal slots at the bottom where enough but the addition of a case fan at the bottom was neccisary. Luckily this lines up perfectly with the SGI cooling vents and blows directly onto the processor, it being at the bottom of the case. I've obtained an SGI keyboard to go with it. I plan to either upgrade this unit or convert the second Indigo I have to P4 2.4Ghz in the spring of 2005. I also am looking at fitting my SGI O2 with a Mini-ITX P4 board for use as a media player. May 2005 - Bought another Indigo, my third, looks like more metalwork coming up... |
 |
|
|
|