X-Authentication-Warning: delorie.com: mail set sender to djgpp-bounces using -f From: Rugxulo Newsgroups: comp.os.msdos.djgpp Subject: Re: incompatible Date: Fri, 18 May 2012 14:48:18 -0700 (PDT) Organization: http://groups.google.com Lines: 72 Message-ID: References: <30744 DOT 3f7d7aa9 DOT 3ce7ea03 AT aol DOT com> NNTP-Posting-Host: 65.13.115.246 Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 X-Trace: posting.google.com 1337377802 6373 127.0.0.1 (18 May 2012 21:50:02 GMT) X-Complaints-To: groups-abuse AT google DOT com NNTP-Posting-Date: Fri, 18 May 2012 21:50:02 +0000 (UTC) Complaints-To: groups-abuse AT google DOT com Injection-Info: w24g2000vby.googlegroups.com; posting-host=65.13.115.246; posting-account=p5rsXQoAAAB8KPnVlgg9E_vlm2dvVhfO User-Agent: G2/1.0 X-HTTP-UserAgent: Mozilla/5.0 (X11; U; Linux i686; en-US) AppleWebKit/534.16 (KHTML, like Gecko) Chrome/10.0.630.0 Safari/534.16,gzip(gfe) Bytes: 4341 To: djgpp AT delorie DOT com DJ-Gateway: from newsgroup comp.os.msdos.djgpp Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by delorie.com id q4IMF2CB032029 Reply-To: djgpp AT delorie DOT com Hi, On May 18, 1:40 pm, Georg wrote: > On May 18, 8:08 pm, Ster DOT DOT DOT AT aol DOT com wrote: > > > is 64 bit the end or do you think we will get 256 ? > > > and maybe completely different incompatible processors  !? > > I think there are already processors available which use more than > 64bit - but not from Intel I guess. I think 64-bit is here to stay for quite a while (famous last words). All competing processors seem to have already migrated to 64-bit as well. This doesn't count instruction extensions like AVX, of course, which use 256-bit registers. http://en.wikipedia.org/wiki/Advanced_Vector_Extensions > One of the reasons for 64bit is that you can address more than 4GB of > memory. 32-bit Windows typically only let you access approx. 3.1 GB of RAM, maximum. Actually, on this computer here, the max I can allegedly use (in any 32-bit OS) is 2.9 GB. Memory holes, address space, etc. (boring). Linux may be able to use up to 4 GB in 32-bit mode, but I'm not sure. MS does not support PAE access at all (thanks to "driver bugs"), so they are indirectly forcing us to all use Win64 to access more RAM. With PAE, you could theoretically access up to 64 GB (but not all at once, would have to page in and out I guess). AMD64 originally was only 40-bit (1 TB) of RAM capability, but latest versions are 48-bit (256 TB). Long story short, you've already been seeing much more 64-bit editions of Windows than otherwise because of this, but Win8 (finalized later this year) will supposedly still have a 32-bit edition (at least judging from their previews). > The previous processors like 386 provided a VM86 mode to support the > use of several 16bit applications while in 32bit mode. This is what > the Windows XP command window is based on and makes it work so well. XP is very good for DJGPP stuff (esp. thanks to CWS' fixes), but it still has bugs and some annoying gfx limitations. Though it's still far far better than Vista or 7, ugh. Too bad XP is deprecated. > The 64bit processor comes without VM386 mode. So when Windows switches > to 64bit mode it has no way to run a command window in VM386 or VM86 > mode. This has to be emulated in software completely and that is > provided by e.g. VirtualPC. There is partial 16-bit pmode support, allegedly, but I guess MS never bothered. Well, their Win16 stuff was all based atop DPMI anyways, so if there is no DOS, I guess there is no Win16. You can run DOS stuff atop 64-bit Windows, almost natively, with VT-X. Otherwise I don't know, my limited experience without VT-X proves that software only emulation isn't good enough (too buggy). If you don't have VT-X, your best luck is dual booting (to either native DOS or Linux with DOSEMU). > A 64bit processor will usually boot in 16bit mode. So if you boot from > a CD with DOS and have a FAT32 partition on your hard disk you can > work in real mode DOS. MS is basically doing away with NTVDM for various reasons that I can't understand. My guess is that they expect Hyper-V atop VT-X to be a better successor.