There are a number of threads on this forum that basically revolve around the same question: "Why does A4 run so much slower on our new(er)/faster PCs running WIN2K/WINXP as compared to our older/slower machines running WINME/WIN98/WIN95?"
The answer lies in the fact that A4 is a DOS application. Actually, for a given CPU speed, A4 will perform the fastest under MSDOS-5, MSDOS-6, or MSDOS-7. (It REALLY screams running on a new 3000mhz machine running MS-DOS!!)
However, most of us want or need some of the functionality of Windows on the machines that we are running A4 on, and it is really getting more and more difficult to get MS-DOS to run on a "modern" machine. Modern disk drives and controllers and NIC cards aren't very compatible.
Networking in generally is more of a pain under MSDOS (since most of us have forgot how to do it).
Next best option is to run A4 on the fastest machine you can get WIN98 to run on. It is also very difficult to find drivers for a typical modern computer's video hardware and NIC. (It is possible to run WIN98 on a new Dell Dimension for example, but you have to disable the on-board video and NIC and install PCI video and NIC cards that still have WIN98 drivers available.) This is not a bad option if you can live with WIN98, as a lot of "current" windows programs will still run under WIN98, but this is also rapidly changing. (Example: Quickbooks 2006 will only run under WIN2K or WINXP)
Starting with WIN95, the Windows operating systems run in Protected Mode (available starting with 286 processors). But DOS programs need to be run in Real Mode. So there were two choices: shut down Windows, reboot and run in MS-DOS mode (no Windows functionality), or run under Windows in what is sometimes referred to as Windows DOS mode. More appropriately this is called Virtual Real Mode, which runs Real Mode from inside Protected Mode, actually allowing multiple DOS applications to be run at the same time under the Windows OS, each of which think they are the only application running on the machine, and each having their own 1MB address space, with an image of the REAL BIOS interface. (Thus the reason you can run multiple occurences of A4 on the same machine at the same time under Windows.)
Getting back to the original speed question, the reason that DOS applications like A4 run "fast" on a WIN98 machine is the way that WIN98 runs a DOS-based program. The code instructions are actually executed directly on the CPU! This is the reason it is possible to easily crash a PC via an errant DOS program running under WIN98/WINME/WIN95.
Starting with WINNT, there is no longer DOS! WIN2K and WINXP are part of the WINNT family of operating systems. With this family of operating systems, when you open a "DOS" window and get the good old command prompt, you are actually running a Windows application that is a MS-DOS emulator (or simulator). So each and every CPU instruction gets decoded and acted on by the emulator program rather than being executed directly on the x86 CPU. Not much different than running a program that emulates DOS on a system with an entirely different CPU platform (like a MAC). The 10x speed degradation that Mike Konoff documented (when factoring in processor speed differences) in his comparison is fairly reasonable. It can take an emulator program 10 CPU instructions in order to emulate a single instruction executed directly on a CPU.
Good for stability, bad for speed.
To make matters worse, as a lot of people have noted, the DOS emulator supplied with WINXP seems to be even worse than the one supplied with WIN2K.
So, what to do? (possibilities I have tried and am currently using in no particular order)
1) Suffer with WIN2K/WINXP.
2) "Upgrade" to a true Windows program like A5 (bad for those of us with a LOT invested in our A4 applications).
3) Run under Windows98/ME/95 (not a bad compromise if you can get the drivers for your new PC's).
4) Run true MS-DOS.
5) A combination of all of the above (what we are doing here - AKA convoluted mess).
All of the above have various pluses and minuses, and are based on my experience over the last 13 years starting with a rather small application and watching it grow into a monster while upgrading to the various versions of A4 (I think we originally started with Alpha-3), as well as operating systems, computer workstations, and server platforms.
I hope this helps - good luck!
The answer lies in the fact that A4 is a DOS application. Actually, for a given CPU speed, A4 will perform the fastest under MSDOS-5, MSDOS-6, or MSDOS-7. (It REALLY screams running on a new 3000mhz machine running MS-DOS!!)
However, most of us want or need some of the functionality of Windows on the machines that we are running A4 on, and it is really getting more and more difficult to get MS-DOS to run on a "modern" machine. Modern disk drives and controllers and NIC cards aren't very compatible.
Networking in generally is more of a pain under MSDOS (since most of us have forgot how to do it).
Next best option is to run A4 on the fastest machine you can get WIN98 to run on. It is also very difficult to find drivers for a typical modern computer's video hardware and NIC. (It is possible to run WIN98 on a new Dell Dimension for example, but you have to disable the on-board video and NIC and install PCI video and NIC cards that still have WIN98 drivers available.) This is not a bad option if you can live with WIN98, as a lot of "current" windows programs will still run under WIN98, but this is also rapidly changing. (Example: Quickbooks 2006 will only run under WIN2K or WINXP)
Starting with WIN95, the Windows operating systems run in Protected Mode (available starting with 286 processors). But DOS programs need to be run in Real Mode. So there were two choices: shut down Windows, reboot and run in MS-DOS mode (no Windows functionality), or run under Windows in what is sometimes referred to as Windows DOS mode. More appropriately this is called Virtual Real Mode, which runs Real Mode from inside Protected Mode, actually allowing multiple DOS applications to be run at the same time under the Windows OS, each of which think they are the only application running on the machine, and each having their own 1MB address space, with an image of the REAL BIOS interface. (Thus the reason you can run multiple occurences of A4 on the same machine at the same time under Windows.)
Getting back to the original speed question, the reason that DOS applications like A4 run "fast" on a WIN98 machine is the way that WIN98 runs a DOS-based program. The code instructions are actually executed directly on the CPU! This is the reason it is possible to easily crash a PC via an errant DOS program running under WIN98/WINME/WIN95.
Starting with WINNT, there is no longer DOS! WIN2K and WINXP are part of the WINNT family of operating systems. With this family of operating systems, when you open a "DOS" window and get the good old command prompt, you are actually running a Windows application that is a MS-DOS emulator (or simulator). So each and every CPU instruction gets decoded and acted on by the emulator program rather than being executed directly on the x86 CPU. Not much different than running a program that emulates DOS on a system with an entirely different CPU platform (like a MAC). The 10x speed degradation that Mike Konoff documented (when factoring in processor speed differences) in his comparison is fairly reasonable. It can take an emulator program 10 CPU instructions in order to emulate a single instruction executed directly on a CPU.
Good for stability, bad for speed.
To make matters worse, as a lot of people have noted, the DOS emulator supplied with WINXP seems to be even worse than the one supplied with WIN2K.
So, what to do? (possibilities I have tried and am currently using in no particular order)
1) Suffer with WIN2K/WINXP.
2) "Upgrade" to a true Windows program like A5 (bad for those of us with a LOT invested in our A4 applications).
3) Run under Windows98/ME/95 (not a bad compromise if you can get the drivers for your new PC's).
4) Run true MS-DOS.
5) A combination of all of the above (what we are doing here - AKA convoluted mess).
All of the above have various pluses and minuses, and are based on my experience over the last 13 years starting with a rather small application and watching it grow into a monster while upgrading to the various versions of A4 (I think we originally started with Alpha-3), as well as operating systems, computer workstations, and server platforms.
I hope this helps - good luck!
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