Talk:Conventional memory

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This article was originally based on material from the Free On-line Dictionary of Computing, which is licensed under the GFDL.

I've removed this passage:

  1. Note that it is neither a limitation of the PC nor of MS-DOS itself, but only the combination of the two. Non-DOS operating systems such as Xenix and Netware did not suffer from the restriction, nor did MS-DOS running on Non-PC compatible X86 computers. == == ==

It was very much a limitation of the pre-386 PC, if 'PC' is defined in this era as IBM systems using Intel chips. The article itself acknowledges this point and this passage subsequently contradicts it. --Yst 23:46, 2 July 2006 (UTC)

I am once again removing this passage, which has been reinserted. The problem with the generalisation that this was not "a limitation of the PC" is that it was fundamentally a limitation of the 8086/8088 and was in practice a real-world limitation of the 286, in that while addressing up to 16MB was possible, it was generally impractical and almost universally ignored as a possibility by manufacturers. It doesn't matter what OS you run on your conventional XT, the chip still can't address more than 1MB. And it doesn't matter what OS you run on your 286, the chip still doesn't make access to the full 16MB adequately practical to be useful. The paragraphs preceding this one acknowledge these differences. This one makes a deceptive generalisation which confuses the whole account. --Yst 19:11, 3 July 2006 (UTC)

I agree with what you say, but am guessing there was some glimmer of truth within that ill-written paragraph. Maybe it was that Xenix, Netware, and on some machines, MSDOS could use 1 MB instead of 640K. Or maybe it was that on 286s some of these could use 16MB (maybe only by VM swapping or something). I imagine that no OS used 16MB on 286s for normal memory since the 286 architecture was so amazingly broken in this respect. -R. S. Shaw 22:15, 4 July 2006 (UTC)
MS-DOS could use 1 mB of RAM on 8088's, but it required some serious hacking (and soldering on the motherboard) to do so. I don't believe XENIX could use any more than DOS could, simply because it was 100% a hardware problem. I know for a fact that MS-DOS can address much more than 640K, but it can't on an 8088 because of a hardware limitation. And yes, Windows/286 could address 16MB as it was specifically designed FOR the 80286. --AndreniW 02:34, 5 July 2006 (UTC)

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[edit] Confused

Shouldn't this: 1024 KiB of memory (220 bytes) read: 1024 KiB of memory (210 bytes)? Unless I've got it all wrong. Please clarify. -- Ynhockey (Talk) 22:22, 28 April 2007 (UTC)

No, because 1 KiB = 1024 (or 210) bytes, and so 1024 Kib = 1024×1024 bytes or 220 bytes. -R. S. Shaw 05:20, 29 April 2007 (UTC)

[edit] Unit Prefix

Considering the low acceptance of the "binary prefixes" within the industry, and their general unfamiliarity outside of it, I propose reverting the March 6th change of units. Opposing views? Cnj 19:26, 25 June 2007 (UTC)

I've spent the last couple days reading the articles on Intel's past microprocessors and I agree that the binary prefixes should be changed to the more-familiar SI prefixes. I've been dabbling with computers since 1980 and majored in computer science in college, yet this is the first place I've ever seen the binary prefixes used. Granted, they may be more accurate, but from what I've seen these articles are directed to the general reader and therefore should be kept as clear as possible. Using the SI prefixes would mean a couple less articles people would have to read and the inaccuracy is only about seven percent at the GB level. KadrianBlackwolf 04:55, 28 June 2007 (UTC)

[edit] Setty

Isn't this a Unix utility? 130.101.100.100 12:39, 24 September 2007 (UTC)

[edit] Should mention linux and other non-DOS operating systems

The main reason for the 640kb barrier was the need to preserve functionality of legacy code. Linux has no such barrier since it has no need to preserve space for legacy software.

Microsoft spent years trying to break Windows of its 640k legacy code, but it lingered on as device drivers (MSCDEX, DOSKEY, SCSI board drivers, etc) with Win 3.1, Win 95, Win 98 and Win ME. I believe Windows NT was really the first Microsoft OS to break away from the 640k barrier. Of course many old programs would not work under NT, but oh well.

DMahalko (talk) 23:26, 31 December 2007 (UTC)