Questions tagged [intel]

For questions about retrocomputing hardware and software created by Intel

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4
votes
0answers
151 views

Scaling compute times to a Pentium III 700 MHz [closed]

According to a competition programming site, where users can submit single source files to be compiled and run, "programs are run on a modern processor but times are scaled to a 700 MHz Pentium ...
4
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1answer
137 views

How much RAM was sold each year in the 1970s?

I'm trying to get an idea of the quantitative parameters of the computer industry in the era that saw the rise of personal computers. Of course, the industry as a whole was old by then; companies like ...
18
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2answers
3k views

How did AMD's 386 and 486 perform like Intel's newer generation?

AMD really started to come into its own as a competitor to Intel around the time of the Intel 80486 introduction. AMD countered Intel by shipping the popular (at least with PC enthusiasts) Am386-40, ...
7
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1answer
496 views

80387 transistor count

In 1985, Intel released the 80386, a particularly complex and sophisticated microprocessor for its day, consisting of 275,000 transistors, a rather large number for the day. How many transistors went ...
2
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1answer
108 views

Intel vs Motorola device communication protocols

On this page about "An S-100 68000 CPU Board" it is said: From a hardware perspective there are some very significant differences how Intel and Motorola CPU's talk to the world. Somewhat ...
2
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0answers
85 views

advice for retrieving functions and tables from intel 8061/8065 bin file (reverse engineering) from Ford EECV ECU

I have under my disposal some Ford EECV bin files and my goal for the next few weeks is to retrieve the functions and tables and plot them out before going onto DIY hardware . . Does anyone know which ...
30
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4answers
9k views

Intel CPU bug in the '90s

My teacher who teaches "Logic" at the university told us a story about Intel processors, which goes: In the '90s Intel had a bug in the calculation of mathematical functions like sin/cos ...
14
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5answers
2k views

How and why did Intel make the PCI bus “CPU Agnostic”?

Intel invented the original 32/64-bit PCI bus in the early 1990s to replace the decade old ISA bus used in PC's. It was immediately popular (in comparison to Micro Channel or EISA), being both faster ...
4
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1answer
297 views

Instructions added with the Intel 80286 [closed]

The 80286 processor added these instructions: ARPL, VERR, VERW, LAR, LSL, SMSW, SGDT, SIDT, SLDT, STR, LMSW, LGDT, LIDT, LLDT, LTR, CLTS. To help understand how this was implemented I am looking for ...
13
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1answer
1k views

Intel processor transistor type evolution

The Intel 4004 used MOS (metal–oxide–semiconductor) transistors. What has been the transistor types used in Intel processors onwards from the 4004 to 8085 to the x86 family of instruction set ...
0
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1answer
118 views

Carry flag in the Intel 8008

Datasheet for the Intel 8008 CPU mentions that the Carry (C) flag is affected with the logic operations (AND, OR, XOR), but it does not make any sense. I believe Carry will be zeroed, but I have no ...
3
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1answer
330 views

Intel 8008 stack behavior

Intel 8008 CPU has an internal stack, implemented as an 8 x 14-bit scratchpad. How does it work exactly? Is there any "invisible 3-bit stack pointer"? I want to know what happens when the ...
4
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0answers
172 views

Undefined opcodes for the Intel 8008 CPU

What happens when I8008 CPU reads the "undefined" opcode (22h, 2Ah, 32h, 38h, 39h, 3Ah)? Are these opcodes evaluated as a NOP instruction, or lead to some side effects (RESET, etc). How many ...
-3
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2answers
446 views

Should I install Gentoo i586 packages on my PC? [closed]

I've recently commenced revitalizing an HP Pavilion Slim. She's running an Intel Pentium, x86_64. I thought I'd give Gentoo a go because I've found it very appealing and as a Bedrock user I wanted to ...
5
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1answer
271 views

Do all Intel Celeron processors support “FCOMIP”? [closed]

I am interested, did all Celeron processors support the FCOMIP instruction? I've made a compiler for my programming language and it uses FCOMIP for every floating-point comparison. I've noticed that ...
2
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1answer
177 views

Are all Slot 1 motherboards compatible with Coppermine?

I want to put together a Pentium III tower using a beautiful Coppermine SL3XL CPU I found with a Slot 1 form factor. However, I noticed that many slot 1 motherboards do not officially support ...
1
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2answers
349 views

What’s the last x86 CPU that didn’t place a limit on the size of a single instruction?

Although useless, it’s widely known the first Intel and derivative CPUs like the Z80 didn’t set a limit on the instruction size. This means that it was possible to fill the whole RAM/ROM with a single ...
41
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4answers
9k views

Is it true that Pentium III was faster than its successor Pentium 4?

My friend told me that earlier iterations of the Pentium 4 were not as fast as the Pentium III, but he didn't have sources. Is it true that the Pentium III was faster than its successor Pentium 4?
16
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2answers
2k views

What are these weird long ISA slots on this 386 board? (not VLB)

In this image, you can see, from the right, a 16-bit ISA slot (occupied by a controller card), an 8-bit ISA slot, four more 16-bit ISA slots, and two of these strange slots that look like a 16-bit ISA ...
20
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2answers
6k views

Why did Socket 3 have more pins than needed for the 486?

Intel's Socket 3, used for 486 processors, was a 19×19 pin grid array socket. However, all compatible processors, to my knowledge, used 17×17 PGA packages. What was the point of the extra pins around ...
8
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1answer
389 views

Which computers used the Intel 82786 graphics chips, and what sort of commercial success did that chip attain?

In the late 1980's, Intel offered the 82768 graphics chip, with specific support for windowed environments. I remember it being covered in Byte magazine, but don't remember seeing any applications of ...
8
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2answers
2k views

First x86 Software Development Manual

These manuals are now called “Intel® 64 and IA-32 Architectures Software Developer Manuals”, and the current version is 71. What was the original name of this manual and when was it released?
69
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7answers
19k views

How much better was DEC Alpha than contemporary x86?

The DEC Alpha, released in 1992, seems like an early implementation of a fully 64-bit microprocessor architecture. Its release led to quite a bit of both marketing hype and genuine vendor support in ...
11
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1answer
877 views

What is the history of the Intel 8275 video controller?

The highly popular at the time build-it-yourself home computer Radio 86RK, designed in the Soviet Union, contained a rather mysterious video controller chip KR580VG75. It had a high end, feature rich ...
4
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5answers
2k views

Real mode flat model

I am interested in old Intel processors. I'll try to be as concise as possible. I have been studying both Jeff Duntemann's Assembly Language Step-by-Step - Chapter 4 and Modes of Memory Addressing on ...
5
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2answers
659 views

Need circuit - manual step-by-step clock for 8086/8088

I finally bought a ceramic 8086-1 (from ebay, from China - I'm not sure that it is not fake chip) and 8284 (it make the necessary synchronization signal for the processor from the crystal). Now I ...
1
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2answers
574 views

What 486 motherboard is this, with American Megatrends BIOS identifying is DPAQ-6156-043090-KF?

I've got an early 486 motherboard that doesn't seem to have a manufacturer name or FCC number on it and I'm having trouble identifying it. I've placed some photos of the motherboard in this Imgur ...
27
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3answers
6k views

Why did Intel abandon unified CPU cache?

When Intel introduced the 80486 in 1989, they included their first on-chip cache, ostensibly to compete better with Motorola, who had been including on-chip caches for 5 years (MC68020, 1984). Unlike ...
4
votes
1answer
633 views

What was the first Intel x86 processor with “Base + Index * Scale + Displacement” addressing mode?

As the title says, what's the first x86 processor from Intel that supports the following addressing mode? mov %reg, 8(base, index, 4) ^^^^^^^^^^^^^^^^^ where the content of %reg will be ...
22
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2answers
6k views

What was the last x86 CPU that did not have the x87 floating-point unit built in?

This Wikipedia page says the following: Most x86 processors since the Intel 80486 have had these x87 instructions implemented in the main CPU So the above quote implies that some CPUs that were ...
4
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1answer
306 views

List of Intel microchips

Where could I find a list of all of the microchips released by Intel, including microprocessors, Rams, roms, storage devices. Etc. I have checked Wikipedia, and they have the processors, but not any ...
17
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1answer
2k views

Which undocumented 8085 instructions is Steven Morse referring to in “In The Beginning”?

In S. P. Morse's 1980 allegory, "In The Beginning", he writes And Intel said, "Let there be an 8085 with an oscillator on the same chip as the processor, and let an on-chip system controller ...
8
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2answers
712 views

When did Intel undergo the SEX change?

I am reading the book "The 8086 / 8088 Primer Second Edition" by Stephen P Morse. In it on page 54, it says The 8086 provides instructions to facilitate the task of sign extension. These ...
13
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1answer
475 views

SYSENTER/SYSEXIT broken on Pentium Pro and Pentium II?

I was just What is linux-gate.so.1?, and it says this Intel recognized this problem early on and introduced a more efficient system call interface in the form of sysenter and sysexit instructions. ...
6
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1answer
788 views

What instructions for the 8086 and subsequent x86 CPUs are not available in Long Mode?

I know from this answer that, Modern x86 CPUs are binary compatible with 8086. You can literally run 8086 binaries on a modern PC, in real mode. (The species analogy is a stretch here, but works ...
7
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4answers
1k views

Reason behind “ASCII Adjust” instructions being ASCII and not BCD?

I'm just curious if there was ever other instructions that were more ASCII-centric than the CISC associated ones we're left with now? Specifically, all the Binary Coded Decimal (BCD) instructions ...
5
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3answers
2k views

Is BX the Base Address Register, and if so why?

I've seen a lot of posts on BX. I believe today, it's a "General Purpose Register". I'm confused at why people call it the Base Address Register, Why it's called the Base Address register, ...
7
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0answers
358 views

How was the Intel 80486 debugged? [closed]

How was the Intel 80486 (from 1989) debugged? I'm assuming it was written in some HDL language, like Verilog. However, how was testing and debugging of the CPU carried out? Were there several steps ...
9
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2answers
641 views

8086 pinout and address space limit

It is tempting to say - and I have said - that Intel made a mistake in the design of the 8086 and 8088, in going from 16 bit addresses to only 20 bits; if they had even shifted the segment registers ...
9
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1answer
669 views

Is there any reason to chose ES, FS, or GS over the others in real mode?

The Wikipedia page on X86 Memory Segmentation says In real mode, the registers CS, DS, SS, and ES point to the currently used program code segment (CS), the current data segment (DS), the current ...
21
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2answers
5k views

The start of x86: Intel 8080 vs Intel 8086?

Why is it said that all modern Intel processors of the x86 family are said to descent from the Intel 8086 and not the Intel 8080? From the Wikipedia article on the Intel 8086, The 8086 gave rise to ...
10
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3answers
1k views

Intel 8080 - Behaviour of the carry bit when comparing a value with 0

I'm in the process of writing an emulator for the Intel 8080. The description of the CMP instruction from Intel's 8080 programming manual (see page 20) says the following: The specified byte is ...
5
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2answers
369 views

Measuring CPU usage on an pSOS operating system

I have a piece of computer hardware in my lab that is running an Intel Celeron CPU with 300 MHz and 128k bytes of secondary cache. The hardware documentation says it's running an real time operating ...
29
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5answers
8k views

Are MS-DOS and Windows 9x vulnerable to Meltdown?

In an interesting crossover between current events and Retrocomputing, the vulnerability known as "Meltdown" was publicly disclosed on January 3rd 2018. The retro-computing tie-in is that this ...
13
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5answers
2k views

Was there ever a genuine “mainframe-on-a-chip” microprocessor?

In the 1980s and 90s, there was a fad among the IT industry press to dub the newest "hot" microprocessor on the market as being a "mainframe-on-a-chip". I have seen this fawning description applied to ...
5
votes
1answer
302 views

Collection of older EPROM IC's

I acquired a collection of older EPROM IC's and am wondering what the rarity of them are or if they are rather common. Do people collect these items? 89142 NM27C512Q ~~ B9212 NM27C512Q ~~ B9312 ...
28
votes
9answers
10k views

Should 486s have a heatsink?

I'm building a 486 computer. I plan on using a 100 MHz 486-DX4 that I have which I believe is about as fast as 486's went. The motherboard I will use (Socket 3) appears to support putting a heatsink ...
3
votes
0answers
729 views

What are some programs known to take advantage of Intel MMX instructions? [closed]

Although MMX techology, introduced in 1997, is long superseded by SSE series of extensions, it's still included in every modern x86 CPU for backwards compatibility. What are some examples of ...
46
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3answers
8k views

What's the relationship between early 90s Pentium microprocessor and today's Intel designs?

My simplified understanding of the evolution of the Intel processors over the last 20 years is that the Pentium II and Pentium III architectures were sort of "dead-ends", and today's Intel processors ...
10
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2answers
1k views

When specifying Intel 80x86 instruction execution time, what is included in the cycle count?

I'm looking at this summary of the Intel x86 integer instruction set (though the same data seems to have been published in a number of places), which gives instruction timings on a per-instruction-...