Universal SGI disk solution: 15kRPM 300GB SCA SCSI drives


Feb 4, 2019
Common wisdom (based on lots of discussions in chat) is that a more or less universal solution to storage on the SGI MIPS machines is the use of cheap and available 15kRPM 300GB 80 pin SCA connector SCSI drives, with an 80 pin SCA to 50/68-pin adapter if necessary.

Specifically I am using the Seagate ST3300655LC (which can be found cheaply on eBay brand new) and:

As I go through my systems and replace the drives with this solution, I will mark off compatibility. If you have a system (whether or not it is in the table below) and you have had success or failure with this combination, please post and I will add it to the list! Please note which SCSI bus / adapter the drive was on, if applicable.

SystemSCSI adapterWithout 80 to 50/68 adapter boardWith 80 to 50/68 adapter board
Challenge LN/A☑ Successful (unknown adapter)
Indigo 1
Indigo 2MotherboardN/A☑ Successful (unknown adapter)
IndyMotherboardN/A☑ Successful (50/68 pin combo)
O2Motherboard☑ SuccessfulN/A
OctaneMotherboard☑ Successful
FuelMotherboardN/A☑ Successful (68 pin non-combo, see Note 1)

Note 1 (Fuel 80 to 50/68 pin adapter): I have not had success with the Fuel and the 50/68 pin combo adapter personally. The drive does not spin up if the SCSI cable to the host is connected, but will spin up if it is not connected; I have also found similar older posts by others. However, others (e.g. LarBob) have reported success, and I also had success after ordering the 68 pin non-combo adapter. It may be that not all adapters are created equal?
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Feb 8, 2019
Probably worth noting that I have had success on the Fuel with that drive and a 68pin adapter board. There seems to be some variance within those adapters somehow.


irix detailer
Feb 8, 2019
I have used them, without any issues in :

1. My O2 (two of them)
2. My Octane
3. My Challenge L
4. My I2i Max
5. My Fuel

They have used various cheap adapters to get the SCA where it needs (SCSI SE 50 pin, 72 pin) to be (except for O2 and Octane).

The Drives I used were called like "HP 412751-016 300GB 15K U320 HDD *New Bulk*" I see there are some compaq branded ones. They all work very well and are very quiet.


Feb 4, 2019
I have used them, without any issues in : [...]
Good info!

Do you know what adapters you used in the Challenge L and Indigo 2 Impact? Also I remember you had to take care with the Challenge using the SCSI SE interface to avoid burning it out on the HVD interface. What SCSI adapter was that; motherboard or expansion card?

It might be good to post some info about connecting it to the correct interface to save others some pain!


Feb 8, 2019
I second this. I've bought several of these drives from various eBay vendors. At this point it's the only type of drive to buy for SGI gear.

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