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Where to put extra connected internal drives when all your drive bays are full

Bill-kun

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Wishful power-fantasy thinking? Maybe. But if you've seen that #retrobattlestations picture of 3 IBM 5150-era cases next to each other with the caption "This is all one computer," or words to that effect, and the explanation by the posting person, then it means it's possible and has been done.

Fast-forward to circa 1990 tower cases. So, the general question I have is, if all the drive bays in the native case are full, and I still want to connect other internal 5.25-size drives (Zip drive, magneto-optical drive, tape drive, whatever), what is the easiest way to physically do it? Is it just getting an additional computer case with its own power supply and running the controller cables from an open expansion slot from case 1 into an open expansion slot in case 2?
 
If the drives are on a SCSI interface, SCSI enclosures are basically just that: a set of drive bays with a power supply and a pair of external SCSI connectors with a cable running between them. Attach drives to the enclosure's internal cable and then run a SCSI cable from the computer's SCSI controller to the enclosure and the controller should be able to see all the drives. It is very easy to do and many of the drive types mentioned will be SCSI. I recommend having an external SCSI terminator to permit multiple enclosures to be chained without having to open up and change the termination of a drive inside any enclosure.

The 5150 and a number of other computers went one step further. The main chassis had a card with a cable carrying the entire bus out to an expansion case. As far as the computer was concerned, the addition of the IBM 5161 turned the classic IBM PC into a system with 4 full height drive bays and 11 slots (really, 13 slots but a slot in each case is required for the cable that connects the boxes). With newer systems, getting an expansion case to work without major issues can be challenging.
 
what is the easiest way to physically do it?


Get a bigger case. You can still buy NEW beige monoliths on ebay for a reasonable price: https://www.ebay.com/itm/183780117051 ( that seller has several different versions, some atx, some inbetween)
 
SCSI has been answered. For SCSI this is "simple".

For the others, the real question is how long can the drive ribbon cables be. Are they spec'd to be long enough to leave one machine and sneak in to another.

But, also, I would think you would need additional controller cards. Most stock ones could only handle 2 to 4 (which most cases could readily accommodate).

If you're talking Zip drives, didn't those use parallel ports?
 
floppy disks and MFM drives (and SCSI) were designed when long cables were the norm.
They can be many feet with proper termination. I used a floppy at the end of a 10 foot cable. no problem.
IDE is 18 inches IIRC.

joe
 
Thanks for mentioning the IBM 5161. It's irrelevant to me, but I never knew about it. I suppose that's what that retrobattlestation was using, twice over. For those interested, here is is a website that has a bunch of manuals and articles about the 5161. http://www.computinghistory.org.uk/det/21352/IBM-5161/
And a great YouTube show-and-tell video. https://www.youtube.com/watch?v=AjYHBsnznVU

SCSI has been answered. For SCSI this is "simple".

For the others, the real question is how long can the drive ribbon cables be. Are they spec'd to be long enough to leave one machine and sneak in to another.

But, also, I would think you would need additional controller cards. Most stock ones could only handle 2 to 4 (which most cases could readily accommodate).

If you're talking Zip drives, didn't those use parallel ports?

I am mostly talking about using additional controller cards since almost all the drives I'm mentioning have IDE connectors. Hence the need to learn about how to make them all not collide in data transfer. Zip drives did first use parallel ports, but mine is a 250 MB. internal IDE Zip drive.

I do have an SCSI controller card that I am going to need to use for a 50-pin SCSI internal magneto-optical drive someone gave me. That is the only one that is SCSI. The rest are all IDE.

I don't suppose there is such a thing as using an SCSI cable to an SCSI enclosure, then somehow also having IDE drives in that as well connected via the SCSI? If not, then I guess I just need a really long IDE cable or two to reach to the said enclosure (or second case).
 
There were adapters that would convert IDE or SATA drives into a SCSI device. Attach the adapter and the drive will work like any other SCSI drive. Some, mostly early, IDE drives might not be handled by the adapter so double check the adapter's requirements before purchase.

Unfortunately, finding one now at a reasonable price seems difficult. What is a reasonable price? Less than what it costs to buy another computer to handle the drives over a network.
 
short answer, no.

instead of scsi, i'd look at USB. usb/IDE adapters are cheap as chips.
 
short answer, no.

instead of scsi, i'd look at USB. usb/IDE adapters are cheap as chips.

USB wasn't a thing in 1990, that may be a problem.

There are IDE drivers for DOS out there, but working with anything other than a standard thumbdrive may prove problematic.
 
I should point out that USB/SCSI adapters were very flakey and came with major restrictions like devices could not be added or removed after bootup. USB/IDE adapters were much better but the ones I have used did not like IDE drives from the early 90s or earlier.

IDE to parallel port adapters used to be quite cheap and worked perfectly with DOS. However, chaining parallel port devices didn't always work. Expect to only have a single device hooked up to a parallel port.
 
Way back in the old days I purchased and IDE adapter, cable, and external enclosure for IDE optical drive and it worked fine. The adapter even had 2 RCA cables so you could get CD audio into the system. I think pre ATA/33 IDE was more forgiving with cable lengths.

90's era tape drives can be found with parallel port external cases, same with ZIP drives.
 
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