Powerbook HDD hack in the works

[techknight]

Hey guys, I decided to spring for a 2004ish era 2.5" Seagate Savvio series U320 HDD that they used in the old IBM blade servers. These are all over ebay for pretty cheap prices.

ST936701LC series. 36.4GB

Now-a-days its SAS using the SATA interface.

Since they are SCA-80 drives, they wont just "plug right in" I found the user manual to the HDD that explains the hard disk and its protocol in full detail, it supports backwards compatible SE mode, and supports narrow transfer bus. So we are good there the firmware supports different modes and the OEM can set which mode the drive defaults in, OEM or not the drive can be set to operate in other modes via firmware which i may have to setup using SCSI utilities so itll default in narrow mode.

It wont be exactly easy because I am going to remove the connector and replace it with a rewired connection that will plug into the SCSI connector for a powerbook, and since the LC version of the drive has no termination, i will have to device termination resistors at the PCB end.

Also, the next hardest thing is the fact that these drives require both 5V AND 12v. they spin/idle at relatively low currents, but at spinup time they could pull a maximum of 2 amps for a fraction of a second until it reaches speed.

Hopefully this hack works out, it might take some modifications in the power circuitry department to make this little guy go. But before i start hacking away at the drives, I have adapters that will take the SCA-80 to 68, and then a 68 to 50 with termination. So, i can goof off with it first before i start hacking away.

 

[Trash80toHP_Mini]

Nice project! I'll have to look at them to use in my Stack-o-LC MoBos in the BrickOven™

How cheap is "pretty cheap?"

 

[techknight]

well i bought a lot of 5 for 37 dollars shipped.

 

[techknight]

ok, well this project is put on hold until further notice, Ran into a non-selling seller on ebay, who sold me the item then claims to not have it. Lovely.

 

[Trash80toHP_Mini]

That happened to me once, there was a 1400c listed as having a G3, theysent me a stock cs. However they looked around for the original and sent me my first/onliest Kanga to make up for the boo-boo.

I was happy then and several times since as a repeat customer! :approve:

 

[techknight]

Well in my case, I had to file a paypal claim because i never got a payment refund or anything. just an apology and that was it.

 

[Bunsen]

I am going to remove the connector and replace it with a rewired connection

How tall are the drives? I think the SCSI Powerbooks can take up to a 12mm drive - if these are 9mm drives, would it be feasible to make up an adapter PCB (or even a ribbon cable) that mounts under the drive? The drive could go in backwards, connecting to the PCB at the far end, and then the PCB mounting a socket for the motherboard ribbon at the "back" end. The PCB could have SMT termination resistors onboard, and connect points and/or a regulator IC for extra power.

Making an adapter would allow easy replacement of the SAS drive without needing to perform the mod on every one. The same board with a 2.5"-3.5" SCSI adapter could be used in a desktop Mac.

 

[Bunsen]

Darn. It says here that they are 15mm drives. You may have issues fitting them into a Powerbook at all :/

Also, being as these are 10,000RPM drives, heat is going to be a major issue. I think you're most likely looking at desktop use only for these. Though - there they would have the advantage of both availability and reduced physical size, so it may still be worth investigating.

 

[Cory5412]

I'm interested in seeing where this goes, but ultimately, in addition to the thickness issue, you may find that none of these disks spin slower than 10kRPM and therefore put out a lot of heat, and also take a lot of power.

This would be really interesting to see followed through as a potential source of disks for external enclosures, or for more well-ventilated modular macs. Especially those PowerPC boxes that'll work with HFS + formatting.

 

[techknight]

Hey bunsen, thats the wrong generation. hehe.

Anyway, ill double-check the data sheets. the PB520 has quite a bit of room in the HDD department.

Regardless, I am waiting for the whole paypal shenanigan crap to work through so i can purchase another set.

 

[techknight]

Well, it appears the older series I was looking into seems to be pretty thick as well:

Once the claim clears, ill buy one anyway just to see if it works electrically, which according to the datasheet, it should.

pix from ePay.