[The Fifth Horseman]

Does that mean that you have to have 16++16 or 8+8 etc. MB RAM? Because I'm absolutely positive my old pentium 133 mhz had 48MB RAM (16+32) and the PC registered all of the ram on the boot.[/b]

Nope. That does not mean that all RAM haas to be paired.
When talking about SIMM (and compatibile EDO) modules, most typical motherboards have four slots, divided in two banks. Note: That can differ, here in front of me I've got a Socket-3 motherboard with 4x30-pin SIMM and 2x72-pin SIMM slots where the 30-pin slots are all a single bank (and thus need four identical modules) and each 72-pin slot counts as two banks, as well as a Socket-5 one with 6x72-pin slots which are grouped in three separate banks.
What I am trying to tell you is that in Pentium architecture, the modules in each bank must be paired - so if you have an 8-meg module in SIMM-1, an identical must follow in SIMM-2 and if you have a 4-meg module in SIMM-3 an identical must follow in SIMM-4.

486 definatelly needed pairs. i had 4+4 at firts but then i expanded to 16+16. for that i needed to remove the 8+8 cause the other slots i had were not for 72pin (i think it was 72) ram.[/b]

Nope, not exactly. As far as my memory goes (combining with info from the manual for my 486 motherboard), the principle about pairing memory in each bank was similar but not identical to that in the Pentium boards.
If first slot of the bank had a module, you didn't have to install one in the second slot of that bank. If, however, you installed one it had to be matching the first one. At least that's how I remember it. I've got the manual for my HOT-433 somwhere around, will see if my memory is right.

Also, the other RAM slots you had were most likely for 30-pin SIMM modules.


Velik: Thanks for clarifying that.


Henning, for the guide:


If motherboard manual is not available, check if the motherboard ID is printed somwhere on it. If it is, put it into Google and more often then not you'll find yourself with at least some of its specs.
If the ID is not printed anywhere, check the markings on the BIOS and chipset and try searching for information on these. This alternative is more time-consuming, but usually gives positive results.
Another alternative (for Windows 9x machines only) is installing EVEREST, as it can identify a huge variety of motherboards and expansion cards.


In several places you've typed in "468" instead of 486.

Equivalent to Pentium 90, runs things meant for Pentium 133 better without any notable slowdowns.[/b]

More accurate would be "Approximately equivalent to Pentium 90, can usually run programs with CPU specification for Pentiums up to 133 without major slowdowns".

The main differences between 486 and 586 processor architecture is implementation of superscalar architecture (which allows 586 to complete more then one operation per clock cycle) and 64-bit data path (which doubles the amount of data that can be accepted from the machine's memory).

Bottom line is:
Programs which were meant for 486 architecture will not experience any particularly significant performance boost when ran on 586 systems.
Early 586 software will function on 486, but slowdowns may occur during intense memory operations and the overall performance will not be as high as on a genuine 586 system.
Later 586 software may refuse to operate on 486 machines altogether.


You should also inform the reader of Pentium Overdrive CPU's (in-depth explanation on Wikipedia). In theory it was supposed to give 486-base systems Pentium efficiency; in practice, it was a failure.
AMD 5x86 and Cyrix 5x86 were produced with the same purpose in mind, and apparently turned out better for the purpose.


My general suggestion is that instead of the current division of the Processor section, you take it like that:
1.2.1 486 architecture (Socket 1-3)
1.2.2 Pentium Overdrive and equivalents (Socket 2-3)
1.2.3 586 architecture (Socket 4 and above)


RAM: EDO modules (there are versions for both SIMM and DIMM slots) are the best option for building a DOS gaming rig. These modules can - depending on circumstances - be up to 40% faster then normal SIMM modules. On Front System Bus speeds below 80 mhz, they beat DIMM modules as well, and even with a 100 mhz FSB the difference between EDO and DIMM modules is minimal.


Sound Card: If you are looking for a genuine Sound Blaster, make sure it's a PRO version. Sound Blaster Pro / Sound Blaster Pro 2 support stereo sound, unlike Sound Blaster / Sound Blaster 2 which do not.
LAPC-I is the best option specifically for MIDI music. It is however apparently very rare, and trying to find one for sale may be very problematic.


Hard Drives:

Note: DOS does not cope well with partitions or drives larger than 1GB. Try and stay below that mark.[/b]

That's simply not true.
What would be correct:

Most versions of DOS are incompatibile with FAT-32 filesystem. This means that they will not be able to access FAT-32 formatted drives.
FAT-16 filesystem can in theory support partition sizes up to 2 GiB (gibibytes; 2^30 bytes; one gibigyte is slightly less then one gigabyte) but it is advisable to avoid its usage on partitions over 400 MB because it's limited cluster count will result in large clusters and that in turn in gross waste of space. (clusters and "slack space" explained on Wikipedia)[/b]

Keyboard: Any AT-standard keyboard will do.


Applications: I agree with Tulac, Norton Commander (or any of its multiple clones) is a MUST on any DOS system. It makes things much easier.
If for some reason you need to take screenshots under DOS, there is an old DOS-based version of Screen Thief. Freeware, don't remember exact version no (will look it up, promise).

For those who use Windows, EVEREST (free download from www.lavalys.com) is a useful hardware recognition tool. It can also read SMART data from your hard drives.
WinImage is another Windows utility. Short and to the point, it can create images of floppy disks and store them on your HDD. Naturally, it can also be used to record said images onto new floppies. This is a good way to preserve things like driver disks for old hardware.


I suggest you add a section on "useful references". Wikipedia is often a useful source of data, http://oldfiles.org.uk/powerload/ is my personal top pick for retro computing resources.