I have a friend who has two servers, a Dell 1800 and an HP 350 ML G5, both have SAS drive arrays. The Dell is a 3.5" and the HP is a 2.5".

They currently only have 3 drives in each array. We want to add additional drives, but they do not appear to have caddies, just "fake" covers. I haven't been able to take a good look at them, so I'm not sure what I need to do here. Are the "sockets" just there, and I can buy additional caddies and just stick them in? Or do I have to buy some kind of caddy adapter?

Also, i'm thinking of just going 2.5" in the new server, so is there a 2.5" adapter caddy that will fit in the 3.5" chassis for the Dell, so I can use 2.5" drives in the 3.5" chassis?

Can I buy 6GB/s drives and add them to the 3GB/s controller? The reason is that we're going to replace both computers in a year or so, and we want to bring the drives with. So rather than buy 3GB/s drives, we just want to buy 6GB/s drives so they can be used in the new server.

  • A Dell PowerEdge 1800? I don't think that server has SAS drives. – joeqwerty Oct 31 '12 at 21:14
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    The OP didn't mention a generation. There's a chance it could have parallel SCSI drives. – ewwhite Oct 31 '12 at 21:19
  • @joeqwerty - You're right.. it's got a PERC 4/DC which appears to be a SCSI U320 controller – Erik Funkenbusch Oct 31 '12 at 21:34

You can buy branded drives from HP and Dell that match the part numbers of your existing disks. If you have bare drives without a "drive caddy" (aka: drive tray, sled, or carrier), you can buy the requisite caddies from HP/Dell parts suppliers or eBay.

As for 3G and 6G disks, you'll pretty much only find 6G SAS drives in the new market because they're compatible with 3G controllers. For a system at that level and drive density, there's no difference between 3G and 6G disks.

Get the right form-factor disks for each server... 2.5" -> 3.5" adapters exist, but it's a janky solution unless you specifically need a 2.5" disk. Many adapters aren't compatible with drive caddies either. In fact, if you don't already have parts, I'd just buy used drives with the identical or spare part numbers of the existing disks.

You didn't provide the model/generation of your Dell server, but for the HP ML350 G5, the disk options and disk part numbers are listed in the Quickspecs for the model.


6Gbps drives are backwards compatible. They will work on a slower controller.

You will need to get the caddies for each server. A bare drive won't work. You should get a 2.5 caddy for the 2.5 drive and a 3.5 caddy for the 3.5 drive.


Generic drives will work fine, you'll need the appropriate caddies, EBay or various 'Net retailers can sell you the appropriate hardware. As for the 3G/6G issues you'll be fine buying the faster disks for both servers.

As for the 2.5 drive in the 3.5 scenario I've never seen those. You might just look at replacing the entire drive cage. I know for the 350 there are aftermarket options you can purchase to change it, i'm not as familiar with the Dell though.

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