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Kickstarter for Amiga/Atari Game Player

commodorejohn

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The Amiga... the irony of the system is that because the chipset is so advanced, it actually gets in the way of the CPU. The blitter and display hardware steal a lot of memory cycles, which makes the CPU come to a grinding halt in some cases.
The Amiga's chipset only uses the alternate cycles that the 68000 doesn't, up to a certain point. I haven't pulled out my copy of the documentation in a while, but I believe it's when you put it in high-resolution mode and/or higher bitdepths or use the blitter that it starts infringing on actual CPU time - IIRC, in 320-pixel mode in 16 colors with no blitter activity, you're entirely free of overlap.
 

1ST1

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Besides, my point was mainly about marketing, regardless of what anyone (including Gary Kildall) thinks, my point was only that I have never seen an IBM PC/XT marketed as a 16-bit machine. I have yet to see evidence to the contrary.

Yes there were some... Olivetti M24, AT&T 6300, Xerox 6060 (they are all technically the same) were based on Intel 8086 with 16 Bit data bus and they even have proprietary 16 Bit ISA BUS. They were sold as 16 bit alternative to IBM XT, twice as fast.
 

krebizfan

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The Amiga's chipset only uses the alternate cycles that the 68000 doesn't, up to a certain point. I haven't pulled out my copy of the documentation in a while, but I believe it's when you put it in high-resolution mode and/or higher bitdepths or use the blitter that it starts infringing on actual CPU time - IIRC, in 320-pixel mode in 16 colors with no blitter activity, you're entirely free of overlap.

Making the chipset that tightly coupled to the CPU performance made it more difficult to replace the CPU with a faster CPU. Counterproductive in the long run.
 

commodorejohn

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No, it was dead simple to replace the CPU - accelerators just decouple from the chipset entirely except when accessing chip RAM. You still hit the bus bottleneck then, but that's just as true of anything trying to maintain compatibility with a legacy bus (see also: every ISA PC.)
 

Scali

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Yes there were some... Olivetti M24, AT&T 6300, Xerox 6060 (they are all technically the same) were based on Intel 8086 with 16 Bit data bus and they even have proprietary 16 Bit ISA BUS. They were sold as 16 bit alternative to IBM XT, twice as fast.

Read more closely: I said "IBM PC/XT", not any clones.
Besides, if they are 8086-based instead of 8088-based, with a 16-bit bus and chipset, then they are indeed fully 16-bit, so there is no problem if they are marketed as such.
 

Scali

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The Amiga's chipset only uses the alternate cycles that the 68000 doesn't, up to a certain point. I haven't pulled out my copy of the documentation in a while, but I believe it's when you put it in high-resolution mode and/or higher bitdepths or use the blitter that it starts infringing on actual CPU time - IIRC, in 320-pixel mode in 16 colors with no blitter activity, you're entirely free of overlap.

Yes, something like that. The CPU uses only the odd cycles, where the chipset uses the even cycles, and odd cycles in some cases, which is basically the copper, blitter, and using the more 'high-end' videomodes which require 'high-resolution DMA' (hi-res or low-res with more than 4 bitplanes).
Also, there was the option of fast RAM, which could not be accessed by the chipset and therefore had no CPU waitstates.
The design of the common Amiga 500 did not allow adding fast ram via the trapdoor though, so software generally had to be designed to run entirely from chip/slowram.
So in practice this meant that using the blitter would cut into the CPU performance.
 
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Scali

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Actually you said, "machines built around an 8088 were never marketed as 16-bit machines." -- not just IBMs.

InfoWorld, Oct. 22, 1984:

That does not look like an actual ad from ITT, but rather some news report from Infoworld themselves.
Besides, I'm not going to bother with every single clone builder here. There may have been some that sold lies, the exception that proves the rule. General consensus was that IBM PC/XT machines were 8-bit class.
 

vwestlife

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I'm not going to bother with every single clone builder here. There may have been some that sold lies, the exception that proves the rule. General consensus was that IBM PC/XT machines were 8-bit class.

There's no use in anyone trying to win the argument here, because you keep changing the parameters of the discussion to suit your pre-determined conclusion. First you made the blanket statement that "machines built around an 8088 were never marketed as 16-bit machines". Now you say "I said 'IBM PC/XT', not any clones" and use the weasel words "general consensus" and "8-bit class".
 

Scali

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There's no use in anyone trying to win the argument here, because you keep changing the parameters of the discussion to suit your pre-determined conclusion.

No I don't.
You see, you don't understand about human interaction and generalizations.
What I meant to say is exactly what is in the book I linked to: PC/XT machines are seen as 8-bit systems. To my knowledge, IBM has never advertised them as being 16-bit.
I have always said '8-bit machines' (as in '8-bit systems' or '8-bit class'), never '8-bit microprocessors'. You wrongly confused the two. I never changed the parameters. This is just a lack of insight and comprehension on your side.
That is not 'my pre-determined conclusion' as you so arrogantly put it. That is the consensus as it has been over the years, as demonstrated by the fact that it is defined exactly that way in the book I linked to (and probably tons of other books on PC hardware, such as Peter Norton's material). You are making this into a personal thing, while it isn't even a statement I personally wish to represent. I am just mentioning it as a historical context (which is indeed pre-determined, as it was written down in books long before I made my post here, as demonstrated).

Clearly nobody in their right mind would think that I would actually have studied every single advert ever made by every single PC/XT-clone maker when I made that statement, nor that I myself would think that there would or could not be any obscure exceptions to this. That's just common sense given the sheer amount of clone makers and marketing statements that they have produced. You have an issue with taking things too literally and missing the overall context. This comes across as anti-social, especially in the aggressive manner in which you display it.
Having said that, even though you tried, you did not manage to produce any marketing material from any vendor that made any claims that go against it.

So even though I am willing to amend my original statement from:
"Again, machines built around an 8088 were never marketed as 16-bit machines."
To:
"Again, machines built around an 8088 were rarely marketed as 16-bit machines."
To cater for the small amount of exceptions that there may be to this rule, to stop the ...retentiveness of some, so to say.
The original statement still stands because no proof of an exception was produced so far (which is NOT an invitation to continue trying, just to be clear).

I am by no means a weasel, I always stand by what I say. You have been reported. Your repeated attacks, accusations and generally anti-social behaviour are not exactly what I want in a friendly vintage-computing community.
 
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mbbrutman

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Reported? For what?

Grow up and learn to play with others. vwestlife is a valued member here.
 

Trixter

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"Again, machines built around an 8088 were rarely marketed as 16-bit machines."

But even this isn't true. They were always marketed as 16-bit systems. This is what I remember growing up in the USA, an experience that was markedly different than yours in the 1980s but is no less valid.

As proof, try reading the first issue of PC Magazine published in February of 1982: https://books.google.com/books?id=w...SXyAIVTI-ACh3dHwDR#v=onepage&q=16-bit&f=false

It is choked with references to the system as a 16-bit system, from the articles to the advertisements. There are articles describing why "16-bit software is different than 8-bit software", "the move from 8-bit to 16-bit", and Microsoft's own advertisement in the magazine says "software for the 16-bit world". From the very beginning, the system was described and marketed as a 16-bit system, and the industry followed suit. (Please don't try to discredit PC Magazine as a fluke, it was a very respected print magazine for over 20 years. I'm sure if you want more proof we can go digging around other magazines but I'd rather not.)

I also remember the Amiga and Atari ST being marketed as 16-bit systems when they were released, lest you think me biased.

Your repeated attacks, accusations and generally anti-social behaviour are not exactly what I want in a friendly vintage-computing community.

Arguments require at least two people.

It distresses me immensely to see my friends fighting with each other. Can we please talk about bit-ness in some other thread, some other day, under different and more well-defined terms?
 

Scali

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But even this isn't true. They were always marketed as 16-bit systems. This is what I remember growing up in the USA, an experience that was markedly different than yours in the 1980s but is no less valid.

I don't feel like continuing the discussion any longer, but it seems that your references speak mostly about 16-bit software. And indeed, the whole point of an 8088 is that it is software-compatible with an 8086.
And there are mentions of CP/M-86 and MS-DOS, which is QDOS, which is 86-DOS. They are, as the name implies, software for 8086 systems, not specifically 8088.

Perhaps the difference is that I got into 8088-based PCs after the AT was already on the market. It may be that the distinction between 8-bit and 16-bit got stronger because of that (16-bit more or less became equivalent with AT, because of the new 16-bit ISA bus and other changes to the PC-architecture. PCs based around an actual 8086 were extremely rare anyway, it was mostly 8088 before the 286 arrived).
But what I remember is exactly what is stated in the book I linked to, it has never been a point of discussion.
 
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Eudimorphodon

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(Please don't try to discredit PC Magazine as a fluke, it was a very respected print magazine for over 20 years. I'm sure if you want more proof we can go digging around other magazines but I'd rather not.)

January 1982 issue of Byte Magazine, review of the brand new IBM Personal Computer, introductory paragraph:

"What microcomputer has color graphics like the Apple II, an 80-column display like the TRS-80 Model II, a redefinable character set like the Atari 800, a 16-bit micro-processor like the Texas Instruments TI 99/4, an expanded memory space like the Apple III, a full-function
uppercase and lowercase keyboard like the TRS-80 Model III, and BASIC color graphics like the TRS-80 Color Computer? Answer: the IBM Per-
sonal Computer, which is a synthesis of the best the microcomputer industry has offered to date..."


I completely agree that the IBM PC and 8088-based friends were generally considered/called sixteen bit machines in the contemporary literature, and for what I would consider the correct reason, IE, they had a CPU with a 16 bit instruction set architecture. Yes, it's certainly true that "16 bit" was sometimes trotted out as a point of differentiation for marketing when 8086 and better clones started appearing (I think I vaguely recall an ad for the Tandy 2000 that crowed about it being a TRUE 16 bit machine, for instance) and I'm pretty sure I also recall the Amiga and Atari ST aficionados jumping on the "it's only eight bit!" bandwagon, but that doesn't negate the fact that 8088-equipped computers are *functionally* 16 bit. The 8088 is 100% software compatible with the 8086 and only differs in details of the bus management circuitry and the size of the prefetch queue, and nobody debates whether the 8086 is a 16 bit machine. Sure, it's a *slow* one, and the eight-bit bus is certainly a contributor to that, but unless you're actually building a plug-in card for it that technical detail really doesn't matter.

Since when was how something was marketed the ultimate factor in deciding the truth anyway? Marketing is lies almost by definition.
 

Scali

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but that doesn't negate the fact that 8088-equipped computers are *functionally* 16 bit.

No, but that was never the point.
By that logic, 68000-based computers are *functionally* 32-bit as well. But the *systems* aren't seen as 32-bit.
The argument was always about the hardware, never about the software.
I mean, you will agree that the fact that a certain system can run 16-bit software does in no way imply that the system itself has to be 16-bit.
Heck, the world still revolves around x86 processors, which are still capable of running 16-bit 8086 software. Most of them aren't actually are 16-bit though.

Since when was how something was marketed the ultimate factor in deciding the truth anyway? Marketing is lies almost by definition.

My argument was rather the opposite: Since even the marketers didn't really dare to market these machines as fully 16-bit or 32-bit respectively, apparently it was quite a controversial issue.
In fact, the "ST" in Atari ST is said to stand for "Sixteen/Thirty-two", referring to the 68000.
 

vwestlife

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There seems to be a continental difference in perspective here. In Europe, 8-bit machines like the C64, BBC Micro, Amstrad CPC, and Atari XL/XE were more expensive and stuck around longer, thus were seen are more serious competitors to the IBM PC and clones. Plus the European based companies and magazines of course wanted to boast the advantages of their own home-grown systems over the American PC, thus were likely to downplay its 16-bit CPU and dismiss it as no better than its 8-bit competitors because of its 8-bit bus.

Whereas in America, the PC put most of its 8-bit competitors out of business by 1985, and the rest were relegated to elementary schools and toy stores. The PC's takeover of the market was much more swift and complete here, to such an extent that it took just a few short years for the once industry-dominating 8-bit CP/M business computers to completely disappear from the market, and forced objectively superior systems like the Amiga and Atari ST to cling to small niche uses such as graphical design and A/V production. The technical arguments of whether or not the PC was a "real 16-bit machine" were almost irrelevant because the PC's biggest advantage was the IBM logo on the front.

And yes, marketing is more brazen in the USA, as evidenced by Apple touting the Mac's "32-bit" 68000 CPU, and NEC selling the 8-bit PC Engine game console as the "TurboGrafx 16". (But then again, Sinclair tried to claim that the QL had a "32-bit" CPU, despite the 68008's 8-bit bus...)

p.s. If you insist that "machines built around an 8088 were rarely marketed as 16-bit machines", then feel free to find an example in which an 8088 based machine was marketed as an "8-bit machine" or "8-bit system"... because that's the logical conclusion of your argument.
 
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Scali

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There seems to be a continental difference in perspective here. In Europe, 8-bit machines like the C64, BBC Micro, Amstrad CPC, and Atari XL/XE were more expensive and stuck around longer, thus were seen are more serious competitors to the IBM PC and clones. Plus the European based companies and magazines of course wanted to boast the advantages of their own home-grown systems over the American PC, thus were likely to downplay its 16-bit CPU and dismiss it as no better than its 8-bit competitors because of its 8-bit bus.

I'm not sure if that has much to do with it, considering the fact that Atari and Commodore were actually US machines as well.
BBC, CPC and Sinclair didn't see a lot of popularity outside of the UK. Commodore and Atari were the biggest players on the European mainland.
The UK is the only European country that produced any successful platforms at all. But even in the UK, the C64 and Amiga were and still are wildly popular. A lot of classic Amiga games were made in the UK.

Also, the book I referenced was written by a US author...

Whereas in America, the PC put most of its 8-bit competitors out of business by 1985

Perhaps. It would explain why there's no demoscene at all in the US: there simply wasn't any hardware capable of demos in the first place.
Over here the PC was only popular at the office in the 80s. C64s and Amigas were cheaper and the games were much better, so why would you want a PC at home?
The IBM PC simply wasn't a competitor in the home market. Far more expensive than the other options, and far less capable.

p.s. If you insist that "machines built around an 8088 were rarely marketed as 16-bit machines", then feel free to find an example in which an 8088 based machine was marketed as an "8-bit machine" or "8-bit system"... because that's the logical conclusion of your argument.

That is not a logical conclusion, but the logical fallacy known as a "False dilemma".
 
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Eudimorphodon

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The argument was always about the hardware, never about the software.
I mean, you will agree that the fact that a certain system can run 16-bit software does in no way imply that the system itself has to be 16-bit.
Heck, the world still revolves around x86 processors, which are still capable of running 16-bit 8086 software. Most of them aren't actually are 16-bit though.

Okay, so that brings up another point: is a Pentium-based computer a "64 bit system"? The CPU has a 64 bit wide data bus so going by your logic that should be the deciding factor, not the length of its registers. Or, how about some of those Macintosh systems that mixed bus sizes like crazy, like the LCII and Mac Classic II: they have a 68030 CPU, a "32 bit" CPU that transparently supports dynamic bus resizing, and thanks to a diabolical piece of VLSI logic those systems have 32 bit access to ROM, 16 bit access to RAM, and most of the peripherals are 8 bit. How many bits is that "System"?

Personally I sympathize with your position in that I acknowledge that everything downstream of the bus unit in an 8088-based computer is on a bus 8 bits wide, but I can't really 100% agree that it makes the IBM PC an "8 bit computer" and I totally remember them being advertised as 16 bit machines outside of the specific instances where the narrow bus was being pointed out as a performance bottleneck.

My argument was rather the opposite: Since even the marketers didn't really dare to market these machines as fully 16-bit or 32-bit respectively, apparently it was quite a controversial issue.
In fact, the "ST" in Atari ST is said to stand for "Sixteen/Thirty-two", referring to the 68000.

So... let's acknowledge that with both the 8088 and 68000 we're somewhere on slippery slopes between 8/16 and 16/32 bit respectively. Slopes do have a dimension, however, and I'd argue that the 68000 is closer to being a 16 bit processor *despite its 32 bit ISA* than the 8088 is to being an 8 bit one. The 8088 has exactly the same execution unit/ALU/register file/etc as the 8086 and is therefore genuinely 16 bit internally; only the BIU has been swapped out. When an 8088 is actually crunching numbers it's doing it a full 16 bits at a time, exactly the same as its older brother. The 68000, on the other hand, is more of a mixed bag; it has 32 bit long registers and the microcode describes a 32 bit ISA but it processes everything with a 16 bit ALU. Therefore the 68000 never actually does anything 32 bits at a time (other than some address calculations carried out by their own specialized circuitry), so it *is* actually more of a stretch to call it a 32 bit CPU than it is to call the 8088 a 16 bit one. Maybe *just* enough more of a stretch to scare the marketing people?

In any case as previously noted it's exceedingly silly to rate systems by how many "bits" they are anyway because, as noted, that number alone can have only the most tenuous relationship to the actual capabilities of the system. It's understandable how it became so popular in video game marketing given the adolescent male culture that buys game consoles is all about size matters (MOAR == BETTER, always!), but in serious conversations its value is pretty much nil.

It is sort of amusing that even that January 1982 Byte review, which is generally enthusiastic about the IBM PC, points out that its raw performance seems a bit unimpressive. (IE, they note that the BASIC seems hardly faster than Applesoft on an Apple ][, and also mentions it seemingly losing several off-the-cuff tests against a 4Mhz Z-80.) Their enthusiasm seemed to be entirely predicated on the idea that the larger RAM capacity would be the enabling factor the PC had over the competition, and I think they were dead on about that. As capable as a C64 might be compared to a 5150 when it comes to throwing graphics up on the screen you can still hold a much larger spreadsheet in RAM on the PC.

Over here the PC was only popular at the office in the 80s. C64s and Amigas were cheaper and the games were much better, so why would you want a PC at home?

The IBM PC simply wasn't a competitor in the home market. Far more expensive than the other options, and far less capable.

Well, America is the land of working yourself to death, and when PCs started sprouting like mushrooms in offices the allure of being able to take work home became a deciding factor in most home computer purchases made after 1985 or so. And... maybe my memory is getting fuzzy, but I do remember it was somewhere around '85-'86 or so when suddenly the math just stopped adding up for the 8 bit micros. Sure, you could get a C64+1541 for only about $300 or so, but by that time rotgut PC clones with 256k and dual disk drives were starting to break the $1000 mark and for the difference in price you were getting four times the RAM (and trivially expandable), four times the disk space (and the ability to relatively cheaply add a hard disk), an 80 column screen, etc. Sure, it's an apples-to-oranges comparison, the C64 doesn't "need" as much hardware to be useful, but it still comes off looking like not that great of a bargain when you factor in the impossibility of lugging your office work home to it. Being cheap and "good at games" just make it look even more like a toy instead of a real computer.

(Likewise the math ruthlessly undercut the chances of the Atari ST and Amiga in the US. Sure, objectively they were pretty attractively priced for the level of capability you got, but they both cost "about as much" as a complete PC once you factored in a monitor and similar amount of disk storage, but they weren't compatible with the "gold standard", and as the market ruthlessly moved forward through '86 and '87 they actually both started looking a little pricey for what you got, particularly if you wanted a hard disk. When the Amiga 500 came out in October '87 at $699 for just the system unit it was competing against off-brand Turbo XT clones that'd give you dual floppies and a mono monitor for that price; add a color monitor to the Amiga and you can just about have a hard disk in your XT.)

I totally envy the European home computer market for not having the crushing boot heel of PC compatibility pressed on its throat through the second half of the 1980's but that's how it was on the west side of the pond. Pity that.

That is not a logical conclusion, but the logical fallacy known as a "False dilemma".

Well, isn't this entire argument something of a false dilemma? You support the "not 16 bit" conclusion by claiming that they were not advertised as sixteen bit, but in the process you've summarily excluded from evidence all the editorial content that refers to them as such. (The Byte archive is convenient so... here's a review of the TI Professional that says "Like IBM, TI abandoned its own proprietary microprocessors and based this computer on Intel's 16-bit chip instead." And, in fact, if you search for "16-bit" in this issue you will find multiple press releases and ads that refer to 8088 machines as 16 bit.)

16-bit.jpg

(And that really is just one; there's another for Sanyo MBC-550's earlier, there's more later...) There are indeed ads and editorial content that call them "16/8 bit" computers instead of just "16" because of the bus size, but there *is* a good reason they're not advertised as simply "eight bit" (by people who actually want to sell them, anyway) and that is because they are not according to the most accepted measures of a system's "bitted-ness". (IE, register/ALU size and programming model.) But in any case, it seems sort of illogical/dirty pool to site a lack of advertising as support for your position while simultaneously denying that it's valid to apply the same argument in reverse.

Anyway, seriously, can't everyone win here? The PC is a 16 bit computer with an eight bit bus and, by extension, an 8 bit system architecture. I see no harm in someone informally referring to it by either number but apparently that must *really matter* in some way I'm missing.
 

vwestlife

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Anyway, seriously, can't everyone win here? The PC is a 16 bit computer with an eight bit bus and, by extension, an 8 bit system architecture. I see no harm in someone informally referring to it by either number but apparently that must *really matter* in some way I'm missing.

The whole argument started with the debate over whether the 386SX-based FM Towns Marty really qualifies as the "world's first 32-bit games console" or not. I thought that would be a non-issue, given that 386SX-based systems can run "Win32" software, and 386SX-based 486SLC systems were equipped with 32-bit VESA Local Bus slots (I know, because I had one!).
 

Scali

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Okay, so that brings up another point: is a Pentium-based computer a "64 bit system"? The CPU has a 64 bit wide data bus so going by your logic that should be the deciding factor, not the length of its registers.

I am not sure what logic you're referring to, because I never claimed that a single spec would decide the whole thing, on the contrary. Let alone that this would be the data bus.
If anything, the logic is more that in order for an entire machine to be considered X bits, all relevant components must be X bits or more. So, lowest common denominator, rather than the 'peak value'.
I also don't like the continued reference to "my logic" or "my conclusions" or anything.
This is not about me, and all these fallacies aren't even worth a response really.

Well, isn't this entire argument something of a false dilemma?

No, the argument is based on historical evidence such as the book I linked.
It's not an argument at all, people are just making it into an argument because they are contesting something that I considered to be common knowledge.
What is understood, does not need to be discussed.


Again, there is a difference between a microprocessor, software and a system/machine as a whole. I was only talking about the machines as a whole.
Nobody ever claimed the 8088 was anything other than a 16-bit processor (certainly not me, I specifically explained that when I discussed the sprite compiler I wrote for 8088 MPH). So I don't see why this is brought up time and time again.

I will say, people REALLY need to get out more if they think of machines only in terms of the CPU. Really!

but apparently that must *really matter* in some way I'm missing.

For me, it's not the point itself, I don't really care. What bothers me is the way people make this into a personal thing, and make personal attacks at me. Also, people refuse to acknowledge the fact that I referenced a book (by a US author no less), which describes the platforms in exactly the same way as I did.
I don't see why this 'discussion' hasn't ended long ago.
 
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