An Insight into the "Program Too Big to Fit in Memory" Phenomenon When Booting DOS from USB Flash Drive:
I. Preparation: U-ZIP drive with DOS + Windows PE (Yangzhou March);
Host 1: Tualatin / 815 motherboard / 128m
Host 2: nVIDIA 6100 + 410 / Athlon64 3200+ / 512
Host 3: VIAK8M800 + 8237 / Sempron 2800+64bit / 256
Host 4: SiS661FX / P42.66 / 256
II. Start: On Host 1, booting basic DOS + winpe is normal, and booting with config.sys for UMBPCI and config.sys for emm386 is normal;
Runs normally on Host 2.
There are problems on Hosts 3 and 4. They have commonalities: basic DOS can be booted, but config.sys and autoexec.bat cannot be read. After entering DOS, dir is normal, but when entering subdirectories, dir cannot display correct content. Except for commands resident in memory, all.exe and.com files of DOS in the root directory cannot run, and the "program too big to fit in memory" phenomenon will occur. Manually configuring himem.sys, EMM386, or UMBPCI will cause a system crash. But there is a very wonderful thing: these commands (including ghost, vb) pre-placed in the hard disk can run.
Only some like grub.exe have the "program too big to fit in memory" phenomenon. I checked the memory situation of each step in detail on Host 3 as follows:
1. When entering DOS, loading config.sys will have
There is an unrecognized command in your config.sys file
There is an error in your config.sys file on line 1
There is an unrecognized command in your config.sys file
There is an error in your config.sys file on line 2
...
Then the DOS prompt appears, and running those on the root directory of drive A will have the "program too big to fit in memory" or "Bad Command or file name" phenomenon, and grub on the hard disk also has the "program too big to fit in memory" phenomenon.
The memory usage:
Name Total Conventional Upper Memory
-------- ---------------- ---------------- ----------------
msdos 79k 79k 0
command 10k 10 k 0
Type of Memory Total Used Free
---------------- ----------- ----------- -----------
Conventional 638k 89k 549k
Upper 0
Reserved 0
Extended (XMS) 65,472k 65,472k 0
It can be seen that the configuration of config.sys is not successful. Then manually loading himem.sys, at this time the memory usage:
Name Total Conventional Upper Memory
-------- ---------------- ---------------- ----------------
msdos 79k 79k 0
command 10k 10 k 0
device 5k 5k 0
Type of Memory Total Used Free
---------------- ----------- ----------- -----------
Conventional 638k 94k 544k
Upper 0
Reserved 0
Extended (XMS) 288,288k 64k 288,224k
Then loading emm386.exe or umbpci.sys, the result is that Upper Memory and XMS don't change much, and basic memory is eaten up by another 13k (11k for emm386.exe, 2k for umbpci.sys). At this time, running ghost on the hard disk can still start, but grub.exe cannot be started.
The result of Host 4 is the same as that of Host 3.
III. Personal Conclusion: There are two aspects. First, the motherboard has problems with the support for the USB flash drive. This is also the most likely aspect I summarized from the U-ZIP booting of countless hosts in the past three years. As soon as I see what motherboard it is, I know it. Intel basically can boot completely, nVIDIA can boot completely, but for VIA and SIS, I don't have the memory of complete booting. ATI is not used much, so I don't remember. Second, my USB flash drive has problems, but I think the possibility is not high. Can my USB flash drive not recognize what chipset the motherboard of the host it is booting from is? Does it just not like SIS and VIA so much?
IV. Request for Help: Please let the moderator and all experts give reasonable explanations and solutions.
I. Preparation: U-ZIP drive with DOS + Windows PE (Yangzhou March);
Host 1: Tualatin / 815 motherboard / 128m
Host 2: nVIDIA 6100 + 410 / Athlon64 3200+ / 512
Host 3: VIAK8M800 + 8237 / Sempron 2800+64bit / 256
Host 4: SiS661FX / P42.66 / 256
II. Start: On Host 1, booting basic DOS + winpe is normal, and booting with config.sys for UMBPCI and config.sys for emm386 is normal;
Runs normally on Host 2.
There are problems on Hosts 3 and 4. They have commonalities: basic DOS can be booted, but config.sys and autoexec.bat cannot be read. After entering DOS, dir is normal, but when entering subdirectories, dir cannot display correct content. Except for commands resident in memory, all.exe and.com files of DOS in the root directory cannot run, and the "program too big to fit in memory" phenomenon will occur. Manually configuring himem.sys, EMM386, or UMBPCI will cause a system crash. But there is a very wonderful thing: these commands (including ghost, vb) pre-placed in the hard disk can run.
Only some like grub.exe have the "program too big to fit in memory" phenomenon. I checked the memory situation of each step in detail on Host 3 as follows:
1. When entering DOS, loading config.sys will have
There is an unrecognized command in your config.sys file
There is an error in your config.sys file on line 1
There is an unrecognized command in your config.sys file
There is an error in your config.sys file on line 2
...
Then the DOS prompt appears, and running those on the root directory of drive A will have the "program too big to fit in memory" or "Bad Command or file name" phenomenon, and grub on the hard disk also has the "program too big to fit in memory" phenomenon.
The memory usage:
Name Total Conventional Upper Memory
-------- ---------------- ---------------- ----------------
msdos 79k 79k 0
command 10k 10 k 0
Type of Memory Total Used Free
---------------- ----------- ----------- -----------
Conventional 638k 89k 549k
Upper 0
Reserved 0
Extended (XMS) 65,472k 65,472k 0
It can be seen that the configuration of config.sys is not successful. Then manually loading himem.sys, at this time the memory usage:
Name Total Conventional Upper Memory
-------- ---------------- ---------------- ----------------
msdos 79k 79k 0
command 10k 10 k 0
device 5k 5k 0
Type of Memory Total Used Free
---------------- ----------- ----------- -----------
Conventional 638k 94k 544k
Upper 0
Reserved 0
Extended (XMS) 288,288k 64k 288,224k
Then loading emm386.exe or umbpci.sys, the result is that Upper Memory and XMS don't change much, and basic memory is eaten up by another 13k (11k for emm386.exe, 2k for umbpci.sys). At this time, running ghost on the hard disk can still start, but grub.exe cannot be started.
The result of Host 4 is the same as that of Host 3.
III. Personal Conclusion: There are two aspects. First, the motherboard has problems with the support for the USB flash drive. This is also the most likely aspect I summarized from the U-ZIP booting of countless hosts in the past three years. As soon as I see what motherboard it is, I know it. Intel basically can boot completely, nVIDIA can boot completely, but for VIA and SIS, I don't have the memory of complete booting. ATI is not used much, so I don't remember. Second, my USB flash drive has problems, but I think the possibility is not high. Can my USB flash drive not recognize what chipset the motherboard of the host it is booting from is? Does it just not like SIS and VIA so much?
IV. Request for Help: Please let the moderator and all experts give reasonable explanations and solutions.
