Talk:IBM PS/2

message: You should also mention the later models like Server 95, M77, P70, Laptops, and so on. So everybody thinks that the 386 is the upper end of the PS/2 models. And a picture of some computers is missing!
*I'm working on it. :)  - Thatdog 20:56, 7 August 2005 (UTC)
thread_title:  Important things are missing 

message: Is a PS/2 port a type of serial ports? 
13:17, 7 February 2006 (UTC)
thread_title:  Serial? 

message: Is anyone good with making wikicharts/tables?  The section with all the model numbers would be much easier to comprehend if it was in table form instead of a bunch of disjointed sentences.  /Blaxthos 23:30, 11 December 2006 (UTC)
thread_title: Models

message: There was basically two generations of PS/2 models. The first generation 85xx models and then the 95xx models that were known as "Premium" models. I believe the IBM logo changed colour, and the 95 series used IML partitions as compared to the 85 series which used floppy-based reference disks. Also, the premium models used SCSI and IDE, were more modern looking, and were supported at least through 1994. I'll have to dig through my specs, but I think the two generations are significant enough to mention. There was also a IBM PC 700 series desktop (6885 or 6886) that had both PCI and MCA slots as well as a few IBM PC servers (720 or 701?) that had MCA slots, but were not listed as part of the PS/2 family.
NTD 28dec06 03:02EST
:Well...Yes. [History of the PS/2]
:IBM 8641-MZV "Server 520" was a dual Pentium-133 with MCA and PCI. 
:Thanks! 71.193.2.115 (talk) 12:34, 15 May 2008 (UTC)
thread_title:  PS/2 85xx series vs the 95xx series? 

message: This is part of a very long and difficult debate. The PS/2 models 30 (286), model 50 (386), and model 70 (486) had an option for a special IBM hard drive that just plugged straight into the system without a separate power cable or any configuration jumpers.
This drive was not SCSI, and apparently not an IDE, MFM, RLL hard drive, because it has nothing like any of those connectors. It's just one huge card-edge connector spanning the entire width of the back of the 3.5 inch drive. I believe the model 30 used a huge ribbon cable with four ferrite shielding cores to connect it to the main board, but the model 70 had a "planar card" that the drive just slotted right into when the drive was installed into the system.
Some people have claimed it was an ESDI hard drive, but this does not appear to be correct either, since ESDI used similar cabling to the early MFM and RLL drives.
(I recently found some of my photos of my old PS/2 hardware I threw out years ago, and I'll see about posting one of the drive pictures.)
Any ideas? DMahalko (talk) 03:37, 17 August 2008 (UTC)
replies: text: This is what IBM called the "Integrated Fixed Disk and Controller" (MCA ID DF9F) - an RLL hard disk with an on-board controller - analogous to IDE/ATA but using a subset of the 16-bit MCA bus on a 72-pin edge connector. According to this article, the BIOS identified this as an ESDI disk, even though, as you point out, the actual ESDI bus isn't used. However, the on-board controller was very similar to the "real" MCA ESDI controller (ID DDFF) used on other PS/2 models. Letdorf (talk) 23:43, 21 September 2008 (UTC)
thread_title:  Interface on the bizarre PS/2 hard drive? 

message: Does anyone know what the technical difference was between PS/2 72-pin SIMMs and the 72-pin SIMMs used by everyone else? For some reason IBM SIMMs only worked in PS/2s and nothing else. Meanwhile clone SIMMs were not usable in the PS/2.
Since the card edge pinout was identical I would have to assume IBM assigned the pins differently. (Or was it the clones that assigned the pins differently?) 
DMahalko (talk) 19:52, 13 January 2011 (UTC)
thread_title:  PS/2 72-pin SIMMs... vs everyone else 

message: I think that the assertion the Micro Channel Architecture was "closed" needs challenging. 
No only was the architecture fully documented (in fact better than the previous PC/PC AT architecture) but to prove the point, other manufacturers produced "clones" based on it. 
On that basis how can it be closed?  
BTW, whether or not one owed IBM royalties for producing clones is neither there nor there.  That was the case with the previous PC/PC AT based boxes and I can assure readers (I worked for IBM OEM at one stage) that royalties on the previous generations WERE paid!  — Preceding unsigned comment added by 86.134.40.250 (talk) 13:03, 27 September 2011 (UTC)
replies: text: If IBM required third parties to pay royalties to make MCA hardware, then it was certainly not "open," whether documented fully or not. Jeh (talk) 01:34, 30 May 2018 (UTC)

text: I feel kinda silly answering this more than a decade later, but it was during the introduction of these PS/2s that "Open Standards" was even defined in the computer industry. For example "ISA", was derived from the IBM PC AT-bus, was not an official "standard", certainly not one external to the company, until Compaq, with a Gang of Nine named the original AT bus, ISA (Industry Standard Architecture) and simultaneously even proposed its successor, EISA —in opposition to the licensing of IBM's MCA. "Prior to developing EISA Compaq had invested significant resources into reverse engineering MCA, but its executives correctly calculated that the $80 billion already spent by corporations on IBM-compatible technology would make it difficult for even IBM to force manufacturers to adopt the new MCA design. Instead of cloning MCA, Compaq formed an alliance with Hewlett Packard and seven other major manufacturers, known collectively as the "Gang of Nine", to develop EISA." -from Compaq article.  
It should be very obvious in hindsight that MCA was closed, the only reason someone should be confused about this, is that Open Architecture was not yet defined precisely as these MCA machines were coming out. One could not be more wrong about "whether or not one owed IBM royalties for producing clones is neither there nor there". 
Interestingly, as a side-note, IBM never sued any clonemakers for BIOS copying, they settled with such companies. It was Apple v. Franklin (1984) which established that software/firmware, or indeed any "non-human readable" code was copyright-able. This is the first legal establishment of US copyright law in the industry, perhaps a further reason why "openness", especially on IBM's part pre-'84, might be confused, also, a few years later IBM jumped on the bandwagon and started touting "Open Standards" in all sorts of marketing and advertisements, which again might also have been confusing for the OP. It was a complete turnaround after much FUD to the contrary from IBM. 75.71.166.197 (talk) 21:09, 20 February 2022 (UTC)
thread_title:  Micro Chanel Architecture 

message: The PS/2's controversial hardware design was tied to a marketing strategy that was similarly unsuccessful.  During the 1980s, IBM's advertising of the original PC and its other product lines had frequently used the likeness of Charlie Chaplin.  For the PS/2, however, IBM augmented this character with a notorious jingle that seemed more suitable for a low-end consumer product than a business-class computing platform 
Gross, someone make this not sound like a personal essay, please. 71.254.122.149 (talk) 00:15, 16 January 2012 (UTC)
replies: text: And why "controversial"? 31.52.254.10 (talk) 19:24, 29 May 2018 (UTC)
thread_title:  Gross Bias 

message: Their price is very important, but misses from the article. 37.192.250.101 (talk) 05:24, 11 October 2014 (UTC)
thread_title:  Pricing information 

message: So, we have "The Personal System/2 or PS/2 was IBM's third generation of personal computers..." - yet nowhere in this article, or IBM Personal Computer, do we see any discussion of any concept of First and Second generation IBM personal computer. If the AT can be argued to be the second generation, then let's make that argument explicit - or lose this statement.  Snori (talk)
: Agreed. I have changed it with sources from the time describing it as IBM's second-generation PC. DigitalIceAge (talk) 03:06, 21 February 2022 (UTC)
thread_title: Third generation?

message: The article says that IBM did not publish the BIOS source code. I can't be sure about PS/2 BIOS source code but I have a copy of the IBM PC XT/286 manual that has the BIOS source code. Perhaps the article means the Advanced BIOS source code was not published; that makes sense. Sam Tomato (talk) 19:58, 8 October 2017 (UTC)
thread_title:  BIOS source code 

message: Is that true? I know there were some oddball less-than-100% clones that also used the 8086, and even 80186, but previous IBMs (and most full compatibles) jumped straight from the 8088 to the 80286. Does that mean that even the lowest end PS/2s had a full 16-bit architecture? What speed did they actually run at (it seems missing from the article)? And what did that mean for the performance and compatibility vs an otherwise similarly clocked 286 model (and indeed, over a typical XT), other matters like the lower end video card (because of smaller processor address space?) aside? 80.189.129.155 (talk) 01:34, 14 April 2019 (UTC)
thread_title:  Definitely an 8086 in the earlier models, not 8088? 

message: The original IBM PC loses (fails to respond to) some interrupt requests from hardware. I think because interrupts were edge-sensitive instead of level-sensitive. Whatever, the ps/2 fixed that problem. This was one innovation that I think has been lost. I had discovered the problem for myself in practice, and had worked around it by using a backup timeout to trigger polling for the lost interrupt. When Microsoft introduced NT they provided access to their driver authors and I had a talk with the engineer writing the serial port driver, who told me that his driver used the same approach to recover lost interrupts. Thus I imagine the lost interrupt problem has never been fixed, which, if true, is one of the sad things in pc history. I am not sure though, because I do not build that kind of stuff anymore. --AJim (talk) 15:11, 3 November 2021 (UTC)
thread_title:  hardware interrupt handling 

message: In the introduction, as it is, it reads, "Many of the PS/2's innovations, such as the 16550 UART (serial port), 1440 KB 3.5-inch floppy disk format, Model M keyboard layout,..."  
This leaves me confused about some things, I believe the writer's intention is to say the layout of the Model M was more important than the keyboard itself, but...  The Modem M was introduced before and separately from the PS/2 lineup, so it's inclusion here is iffy. The keyboard layout really has little to do with PS/2 Computers, themselves, although feel free to find a published source saying the contrary. 
I think the PS/2 keyboard PORT is much more notable, in specific reference to the PS/2 computers. And also, for instance, how many of the PS/2s actually included an Model M keyboard? (The PS/2 port article also lacks this information) So, I'm not sure how a reference to the "layout" came about. lol I've just talked myself into removing the reference to "Model-M layout".  If someone wants to reference the "layout" in saying that the PS/2 lineup in particular contributed to the popularization of keyboard layout somehow, please reference a third-party source. I'm not going to search for such an external reference for the PS/2 port, because the article link serves as a reference, the references in the PS/2 port article should suffice. I'm noticing more and more decade+ old "citation needed" in Wikipedia articles where a citation isn't actually needed (For example, if the sentence itself mentions a third party source in sufficient detail, a footnote reference is simply redundant). Also a reference at the end of a paragraph may serve for several sentences, not just a single sentence). 75.71.166.197 (talk) 20:37, 20 February 2022 (UTC)
thread_title:  more keyboard information on "layout" ? other quibbles with the introduction 

message: Would be nice to have some info on keyboards, layouts, and picture of what was bundled. 2A02:168:F609:1:284F:5687:CC7:7DF7 (talk) 16:18, 27 January 2024 (UTC)
thread_title:  keyboards available at launch?