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72

TL;DR: It's the pipeline. The 80486 contains parallel operating stages for decoding, operand fetch, execution and write back. So while an ADD reg,reg does take 3 clocks to perform, as it did in the original 8086, its execution overlaps with the previous/next operation, so the CPU can crank out one ADD reg,reg per clock. The Long Read (Caveat, there's a whole ...


32

The extra pins were forward-planning, on both Socket 2 and Socket 3. Most of the extra pins are used for power (Vcc) and ground (Vss), which is useful to provide more power to a CPU. The other pins are keys, a new INIT pin (F19), and signals used for enabling and controlling the write-back L1 cache. (See the socket 3 specifications in the 486 family ...


23

Yes, Intel did make 486SX CPUs with no FPU on the die. You can see the difference in die shots, e.g. from this CPU-World.com thread: early 486SXs are nearly indistinguishable from 486DXs, but later 486SXs are simpler (the right-hand side has been reworked, and is missing the FPU which was in the lower-right-hand corner). This is a 486DX: This is an early ...


20

The Am386 and Am486 were designed as clock-for-clock equivalents of the corresponding Intel CPUs, based on reverse-engineering and AMD’s previous second-source licenses — at least the Am386 even used the same micro-code as Intel’s 80386. The only speed advantages came from higher clock speeds (40MHz v. 33MHz) and, in some Am486 models, the use of write-back ...


18

First, it is not true that the 486 executes instructions in a single cycle. The 80486 is a pipelined architecture, so it's more accurate to say that most instructions can start one cycle after the preceding instruction has started. The pipeline length of an 80486 is 5 stages (IF → ID1 → ID2 → EX → WB). This means that an instruction ...


14

VMWare is not an emulator these days, but a hypervisor. Windows 3.1 is running directly on the hardware with nothing underneath it, just fenced in by hardware-level protection and translation. If you want to slow it down, you'll have to eat up cycles with a busy task, or slow down your processor some other way. Another option would be to use an emulator ...


10

Is it really so simple as just getting to higher clock speeds than Intel did? Yes, it is that simple. Up and including the 486 AMD's CPUs were developed close to Intels devices, supported by in detail information provided by Intel as well as reverse engineering. AMD adapted the design to their production process. This included low level changes in how ...


8

Socket 3 did not have more pins than needed. It was designed to support the Pentium OverDrive CPUs that Intel released in the mid-1990s. These CPUs could have up to 237 pins, while the Socket 3 allowed 238 pins.


7

You might consider DOSBox (free). It is more oriented towards emulating retro hardware, and has some speed control options. It tries to 'figure out' what the speed control should be, but there is a manual setting you can also use if that fails. Additionally, it does have a scaling feature (which I personally prefer over going full-screen anyway -- going ...


7

I've found out the right model. Turns out it wasn't a "ValuePoint" at all. It was an IBM "Personal Computer 330", but at least I remembered the "466DX2" part right... I found this image by searching for something similar to "IBM slide door", after suddenly remembering that slide door thing: https://i.pinimg.com/...


6

As far as I know this laptop can’t easily be connected to a network, which leaves three options for getting software onto it: transfer over the serial or parallel ports, using an appropriate cable and software such as LapLink or the built-in transfer tools in MS-DOS 6.0 or later, PC-DOS 5.02 or later, and DR DOS 6.0 or later; the floppy drive; directly ...


5

Use the following manual for disassembly: http://www.minuszerodegrees.net/manuals/Toshiba/Other/Toshiba%20T1950%20T1950CS%20T1950CT%20-%20Maintenance%20Manual.pdf You have to unscrew about 30 screws. While it is actually difficult to damage something, be careful with the floppy drive ribbon cable. Once you get to the floppy drive (it requires a full ...


5

EDIT 2020-12-01: While I stand by my reasoning, my conclusion below was incorrect. Memory is a funny thing, isn't it? Anyway, @HopelessNostalgic provided the correct answer, please upvote that one instead of this one. To summarize the requirements: IBM PS/ValuePoint or IBM ValuePoint desktop (not tower) "486" or "466" followed by "...


2

There is a usb hdd adapter witch have usual laptop and desktop ide ports (2.5" and 3.5" hdd) Also sata port and usb. You can copy stuff in each of them when connected to a modern Pc. Make sure it has power supply included, if a need transfer from bigger drives as they require more power. I bought this. Just make sure voltage rating suits your ...


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