collector
Experienced Member
I acquired a 5150 - 2 floppy drive computer the other day. I have a seagate st-251 and want to install it. Can this be done and if so how?
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how to install seagate st-251 in an ibm pc
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DOS lives on!!
Veteran Member
I don't think the 5150 can handle hard drives. The power supply doesn't provide enogh juice to run them.
Although usually true I recently aquirded an ST251 in a 5150 and it worked absolutely fine. Just bung in it in place of FDD 2, need a controller obviously, and update the DIP switches on the 5150 m/board to one drive.
Please do post the spare FDD in the sales section if you could be persuaded to part with it!
Please do post the spare FDD in the sales section if you could be persuaded to part with it!
Chuck(G)
25k Member
A lot of 5150 owners (yours truly, included) replaced the 2 FH floppies with 2 half-height floppies and stuffed in a hard drive. An XTIDE setup using a CF or microdrive would certainly be fine and allow you to keep the two FH floppies.
modem7
10k Member
If the 5150 motherboard is the earlier 16KB-64KB type, the BIOS chip needs to be ugraded, if not done already, to the third revision one. Otherwise the hard disk controller will not work. If it has been upgraded, the IBM part number of "1501476" will be found on the chip in socket U33.
As for acquiring an 8-bit MFM (ST506/ST412 interface) controller, if you want to use the full capacity of the ST-251 (820 cylinders, 8 heads, 17 SPT), then not any controller will do - you'll need one that can deal with a drive of 820 cylinders / 8 heads / 17 SPT.
Alternately, certain other controllers will work, but only partially use the capacity of the ST-251. For example, at http://www.minuszerodegrees.net/ibm_xebec/ibm_xebec.htm are shown the various controllers that IBM supplied in the 5160. If you used variation #1 or #2, only 10MB (300 of the 820 cylinders, 4 of the 8 heads) will be used. If you used variation #3, only 20MB (615 of the 820 cylinders, 4 of the 8 heads) will be used.
As for acquiring an 8-bit MFM (ST506/ST412 interface) controller, if you want to use the full capacity of the ST-251 (820 cylinders, 8 heads, 17 SPT), then not any controller will do - you'll need one that can deal with a drive of 820 cylinders / 8 heads / 17 SPT.
Alternately, certain other controllers will work, but only partially use the capacity of the ST-251. For example, at http://www.minuszerodegrees.net/ibm_xebec/ibm_xebec.htm are shown the various controllers that IBM supplied in the 5160. If you used variation #1 or #2, only 10MB (300 of the 820 cylinders, 4 of the 8 heads) will be used. If you used variation #3, only 20MB (615 of the 820 cylinders, 4 of the 8 heads) will be used.
Good point on the BIOS.
Here's some info on the drive. A Seagate ST11M controller was in the 5150 I aquired.
Here's some info on the drive. A Seagate ST11M controller was in the 5150 I aquired.
Chuck(G)
25k Member
If you don't mind booting from a floppy every time you start the system, it's possible to use a hard drive without upgrading the BIOS if you have the (non BIOS extension using) older ROMs installed.
I have some spare MFM controllers I could sell to you if you need one. I can send more info on them if you are interested.
Chuck(G)
25k Member
I wonder how many of those ST11M and ST11Rs are just salvage off of hardcards?