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DavidBarnhart
August 29th, 2006, 04:22 PM
After looking for one at thrift stores for three/four years, I finally found an IBM 5150. Pretty pleased, I snatched it up, brought it home, and only then tried to figure out exactly what I had received with it. I've done a bit of reading on these boards already, but there are still a couple questions left over. Seasoned 5150 owners: any help?

1) There's a 256k ISA RAM card. I noted, however, that the DIP switches controlling the memory had been set to the odd configuration of 48k (or something in the 40s...I forget now). Did the 5150s take ISA RAM cards? I assume those DIP switches are off.

2) Sadly, there's no hard drive inside. Also sadly, I'm beginning to think that adding one will be pricey. First, off, what's the biggest drive I can put in this? I believe it has the third bios version. Second, are there any better options than shelling out for a ST-506 sort of drive? Third party controller cards and drives? External drives? Anything but a tape drive. I'm just not sure what this thing can handle.

3) This seems to have been a late PC. I see a little tag inside with a date of mid-1984. Of course, it's not the 16-256 motherboard. Does this mean I probably have the 360k floppies, or did they put even newer ones in them toward the end of the product line? Furthermore, I still have my old 1.2mb 5.25 disks laying around. I think a couple may be blank. I was thinking about trying to reformat them. Were these backward compatible with a 360k drive (albeit at a lower capacity)?

4) The thrift store had both the monochrome monitor and the 5153. So I got them both. I read somewhere that it was possible to do a dual-monitor setup, but I don't exactly see how with the DIP switches. Is the dual monitor thing actually accurate?

mbbrutman
August 29th, 2006, 05:02 PM
1) There's a 256k ISA RAM card. I noted, however, that the DIP switches controlling the memory had been set to the odd configuration of 48k (or something in the 40s...I forget now). Did the 5150s take ISA RAM cards? I assume those DIP switches are off.

The dip switches might very well be wrong. 5150s have some RAM on the motherboard which depends on the age of the motherboard. After that, the ISA cards are the only way to add memory.



2) Sadly, there's no hard drive inside. Also sadly, I'm beginning to think that adding one will be pricey. First, off, what's the biggest drive I can put in this? I believe it has the third bios version. Second, are there any better options than shelling out for a ST-506 sort of drive? Third party controller cards and drives? External drives? Anything but a tape drive. I'm just not sure what this thing can handle.

Don't alter it - find another one that is in less original condition, or find an XT.

If you have to add a hard drive your choices are limited:


You can use a classic MFM controller and drive. These are unreliable due to their advanced age.
You can try to find an 8 bit IDE card and a small IDE drive that will work with it. The cards are rare and it is 'hit or miss' on finding a compatible IDE drive for it.
You can find an 8 bit SCSI card with a BIOS extension that will boot the machine, and a small SCSI drive. The cards aren't that common, but at least you have better options for drives.
You can add an external parallel port attached drive, either SCSI or IDE. You won't be able to boot from it, but it does provide mass storage. Zip drives work as well.



3) This seems to have been a late PC. I see a little tag inside with a date of mid-1984. Of course, it's not the 16-256 motherboard. Does this mean I probably have the 360k floppies, or did they put even newer ones in them toward the end of the product line? Furthermore, I still have my old 1.2mb 5.25 disks laying around. I think a couple may be blank. I was thinking about trying to reformat them. Were these backward compatible with a 360k drive (albeit at a lower capacity)?

I'm not sure what is going on here. If it is a late PC, then it has a late motherboard. How much RAM is on the motherboard, and what is the revision date of the BIOS?

The IBM 5150 in stock condition with period parts only supports 360KB drives. 1.2MB drives won't work, and definitely don't feed 1.2MB diskettes to 360KB drives. (We already have a few threads explaining why that is a bad thing to do.) 720KB 3.5 inch drives are possible with device drivers. And if you add your own controller you can put on whatever the controller supports.


4) The thrift store had both the monochrome monitor and the 5153. So I got them both. I read somewhere that it was possible to do a dual-monitor setup, but I don't exactly see how with the DIP switches. Is the dual monitor thing actually accurate?

The dual monitor setup is possible. The switch on the motherboard only tells the machine what to use by default. Lookup the DOS 'mode' command for how to switch monitors.


Btw, it sounds like a beautiful machine as is. I love machines that have both monitors. Do some background reading on it though .. Scott Mueller's book Upgrading and Repairing PCs is a must. The original IBM Guide To Operations, BASIC and DOS manuals will also be helpful.

DavidBarnhart
August 29th, 2006, 07:39 PM
Great. Thanks for the info. I think I'll leave the PC without a hard drive. I actually have a zip drive laying around. You really think it will work with the 5150 once I get DOS booted? It's a parallel zip drive and all, but that just seems like awfully recent technology compared to the 5150.

Speaking of DOS, what is the latest version that these machines can run? Was there some limit?

mbbrutman
August 29th, 2006, 08:02 PM
The Zip works. Trust me, I've run one on a PCjr. :-)

Iomega's 'guest' program is a little on the fat side. There is a 3rd party driver called PalmZip that is very good for older/slower machines. It works with DOS 2.1 and up, and takes a minimal amount of memory. I'm a happy, registered user of it. The web site is at http://leute.server.de/peichl/palmzipe.htm

That machine should run any version of DOS you can find. DOS 3.3, 5.0 and 6.22 are my favorites.

dreddnott
August 29th, 2006, 08:07 PM
Yeah. DOS 4.x totally sucks the big one.

DOS 5.0 is what I grew up with.

DoctorPepper
August 30th, 2006, 03:28 AM
Yeah. DOS 4.x totally sucks the big one.

DOS 5.0 is what I grew up with.

Agreed! I just don't know what Microsoft was thinking when they came out with MS-DOS 4.x!

I've used 2.x (I can't remember the actual version, but I know it was 2.something), 3.3, 5.0, 6.0 and 6.2.

I still have 6.2 running on a couple of computers, and my Tandy 1400 LT uses 3.3, I believe.

mbbrutman
August 30th, 2006, 05:45 AM
It's always funny to hear the non-programmers criticizing software.

DOS 4.0 was the first IBM or MS version of DOS to break the 32MB partition barrier by using FAT16. It also was the first DOS to have the 'shell' interface.

So, yes it had a few bugs. But sucks the big one or 'what were they thinking' are hardly reasonable reactions when looking back close to 20 years later.

dongfeng
August 30th, 2006, 08:00 AM
After looking for one at thrift stores for three/four years, I finally found an IBM 5150. Pretty pleased, I snatched it up, brought it home, and only then tried to figure out exactly what I had received with it. I've done a bit of reading on these boards already, but there are still a couple questions left over. Seasoned 5150 owners: any help?

Great find! I run DOS 2.00 on both my 5150s, one with hard drive, one without :)


1) There's a 256k ISA RAM card. I noted, however, that the DIP switches controlling the memory had been set to the odd configuration of 48k (or something in the 40s...I forget now). Did the 5150s take ISA RAM cards? I assume those DIP switches are off.

Without the RAM card your machine would probably have 256kB of memory - to find out what is on the card you'll have to investigate the card some more. Usually you can work it out easily enough by googling the numbers on the memory chips. Total Hardware 99 would have settings for your card.

http://www.thegreenhouse.us/th99/

The most common card I have seen is the MINI MAGIC EV-138.

http://www.thegreenhouse.us/th99/i/E-H/52646.php


2) Sadly, there's no hard drive inside. Also sadly, I'm beginning to think that adding one will be pricey. First, off, what's the biggest drive I can put in this? I believe it has the third bios version. Second, are there any better options than shelling out for a ST-506 sort of drive? Third party controller cards and drives? External drives? Anything but a tape drive. I'm just not sure what this thing can handle.

They can be costly, but if you are in the USA they turn up on eBay fairly frequently. Just get one with a matching controller. Also remember if you have the 63W PSU you will have to replace it as it can't cope in powering a hard drive.


3) This seems to have been a late PC. I see a little tag inside with a date of mid-1984. Of course, it's not the 16-256 motherboard. Does this mean I probably have the 360k floppies, or did they put even newer ones in them toward the end of the product line? Furthermore, I still have my old 1.2mb 5.25 disks laying around. I think a couple may be blank. I was thinking about trying to reformat them. Were these backward compatible with a 360k drive (albeit at a lower capacity)?

360kB only. Your 5150 is the same age as mine :)

carlsson
August 30th, 2006, 02:36 PM
But in all fairness, I remember reading in magazines (I might still have them) already "back then" how people were disappointed by MS-DOS 4.0 being big and slow, and reverted to 3.3 while waiting for something better. Sure, those were journalists, not programmers. Not that it has much to do with David's 5150 if he wants to keep it in original condition?

dongfeng
August 30th, 2006, 02:44 PM
August 1984 was DOS 3.0, so your machine probably came with either that, or 2.1 (or 2.11?).

mbbrutman
August 30th, 2006, 05:10 PM
It was bigger and slower than DOS 3.3, but there was a reason for it - it added a lot of new function. FAT16 was the first filesystem revision to DOS since directories were added in 2.0.

So if you didn't need partitions greater than 32MB, you could stay on DOS 3.3.

What I object to is people slamming it without considering the context in which it was introduced. Everything about a vintage computer sucks if you don't consider it in context.

dreddnott
August 30th, 2006, 06:08 PM
Vintage computer keyboards are vastly superior to the modern variety (at least, the IBM ones are!).

Booting into BASIC from ROM when no OS is present is vastly superior to sitting there and doing nothing like modern computers do.

mbbrutman
August 30th, 2006, 06:43 PM
Let's not go completely off topic by discussing how old computers fare compared to newer computers.

People said DOS 4 sucked. At the time, introducing FAT16 was a big improvement. So just knee-jerk saying that it sucked without examining why seems ill-informed. It sucked because it was a major change in the underpinnings of the file system, plus a few bugs.

We're going to look back in many years and say Windows XP sucked too. But without looking at the context, it's a meaningless statement to say that something sucks or rocks.

carlsson
August 30th, 2006, 06:48 PM
No, ten years from now we'll say that Windows ME sucked. Because in some ways, it appears to be the Windows equivalent to MS-DOS 4.0 - a sequel to a popular version, introducing some new features that its successors would incorporate as well, but itself looking a bit clumsy when it arrived.

dreddnott
August 30th, 2006, 07:47 PM
I think people realised that Windows Millennium sucked the big one the day it came out.

DOS 4 might have been a similar situation: I know my dad upgraded straight from DOS 3.3 to DOS 5.0 despite (or perhaps because of) his mother's 286 running DOS 4.0.

Windows XP is a fair operating system, perhaps only because it's some consumer-level goodies (and baddies like activation and WGA) tacked on to Windows 2000, but decent enough to keep things going smoothly for five years.

I don't think people are going to be welcoming Vista particularly much when it finally comes along. DirectX 10? DRM? Revamped security model? No WinFS? 64- and 32-bit support? Excessive sysreqs? It's a hit-and-miss situation, and only time will tell, but I think Microsoft will have a hard time telling people they don't want or need Windows XP/2K anymore.

Mike Chambers
September 2nd, 2006, 04:57 PM
if you use an 8-bit IDE controller, there should theoretically be no limit on hard disk size afaik... i don't see any reason you couldn't install, say... a 200 GB drive.

i might be wrong, correct me if i am! i believe it would only depend on the OSes that thing can handle, and the OS's supported file systems.

dongfeng
September 3rd, 2006, 02:19 AM
The BIOS might have a limit. On my 486, no matter what drive I put in it, I can only use around 400MB of space.

Also, if you are using an XT class computer you might have to find an XT class IDE drive...