Trixter
Veteran Member
I used 4DOS/NDOS to get the free RAM higher; 572K free was possible on my test setup if using 4DOS disk swapping.
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Windows 2.03 on PC-XT Clone
- Thread starter AbsoZed
- Start date
Caluser2000
Banned
Here's vwestlife's free conventional mem. comparison list without any memory managers loaded of various MS/PC Dos variants:
"I just went through all my boot disks, and ran CHKDSK on each one to display the amount of free RAM (out of 640K) on each one, using a totally clean boot (no CONFIG.SYS or AUTOEXEC.BAT):
PC DOS 2.00 ... 630,672 bytes
PC DOS 2.10 ... 630,672
PC DOS 3.10 ... 616,432
MS-DOS 3.10 ... 616,432
PC DOS 3.21 ... 609,392
PC DOS 3.30 ... 600,528
MS-DOS 3.30 ... 600,368
IBM DOS 5.00 ... 593,328
MS-DOS 5.00 ... 593,328
MS-DOS 6.00 ... 592,256
IBM DOS 6.10 ... 593,056
MS-DOS 6.22 ... 592,256
PC DOS 6.30 ... 593,024
PC DOS 7.00 Revision 0 ... 593,840
PC DOS 2000 (7.00 Revision 1) ... 593,760
I also have an MS-DOS 4.01 boot disk, but not a copy of CHKDSK which will work with it, so I can't give it an accurate free RAM amount, but judging by what other utilities report, it's somewhere in the ballpark of 590,000 bytes. So IBM claimed that PC DOS 7 offered the most free RAM of any version of DOS since 3.3, and that does appear to be true!"
DrDos 6.0 gave me 588,544 bytes. I should see what Novell/Caldera Dos's report just out of interest/curiousity.
"I just went through all my boot disks, and ran CHKDSK on each one to display the amount of free RAM (out of 640K) on each one, using a totally clean boot (no CONFIG.SYS or AUTOEXEC.BAT):
PC DOS 2.00 ... 630,672 bytes
PC DOS 2.10 ... 630,672
PC DOS 3.10 ... 616,432
MS-DOS 3.10 ... 616,432
PC DOS 3.21 ... 609,392
PC DOS 3.30 ... 600,528
MS-DOS 3.30 ... 600,368
IBM DOS 5.00 ... 593,328
MS-DOS 5.00 ... 593,328
MS-DOS 6.00 ... 592,256
IBM DOS 6.10 ... 593,056
MS-DOS 6.22 ... 592,256
PC DOS 6.30 ... 593,024
PC DOS 7.00 Revision 0 ... 593,840
PC DOS 2000 (7.00 Revision 1) ... 593,760
I also have an MS-DOS 4.01 boot disk, but not a copy of CHKDSK which will work with it, so I can't give it an accurate free RAM amount, but judging by what other utilities report, it's somewhere in the ballpark of 590,000 bytes. So IBM claimed that PC DOS 7 offered the most free RAM of any version of DOS since 3.3, and that does appear to be true!"
DrDos 6.0 gave me 588,544 bytes. I should see what Novell/Caldera Dos's report just out of interest/curiousity.
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I wonder why they didn't delay Windows 3.0 to add DOS 5.0 support.
Caluser2000
Banned
I'd imagine to try to clobber IBM OS/2 sales.
MS Dos 5.0 was also a reaction to DrDos 5.0 iirc
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The OS/2 2.0 project did not turn into a fiasco until after Windows 3.0 released.
Caluser2000
Banned
Which validates my suggestion. MS where about to split from the project so shipped something that will fill the gap...
Did you forget that MS for example released the MS OS/2 2.0 SDK in December 1989, not that long before Win3.0 released?
Caluser2000
Banned
It's called hedging ones bets. MS were good at that and always had fingers in a few pies. An early form of NT was also in development in parallel with OS/2, which was to be it's successor. Windows 3.0 was a runaway success despite it's flaws.
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