Why didn't modular CPUs ever catch on?

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I salvaged one of these out of an old junk VAIO tower. It looked like the one in the link, except that the bars from the heat-sink were sticking out the other side. So how come modular CPUs never caught on? Seems like a good idea. Just slides right in, no messing with thermal paste.

 

Because the faster CPU's got, the heavier and bulkier coolers got, and the slot CPU's never really caught on and started the trend of LGA/PGA.

 

Modular, you must mean vertical? Horizontal makes more sense anywho.

 

Actually, Slot CPU's did in fact have removable heatsinks: http://upload.wikimedia.org/wikiped...l_Slot_1_(right)-flickr_-_by_-_flickrsven.jpg

 

Pin counts, modern CPUs need a very dense stack of pins that could really only be done either via BGA or the current desktop PGA layout.

 

IIRC, one of the main reasons they had those slot CPUs was because they couldn't practically fit all of the L2 or L3 cache on die (a combination of die size issues and immature process technologies?)... so they had to make these monstrosities to support an off-die cache. Obviously I'm sure Intel advertised it as a feature back then, but as history tells us all, as soon as they could get all of the crap back on a single die, they went back to PGA/LGA.

 

From wikipedia

With the introduction of the Pentium II CPU, the need for greater access for testing had made the transition from socket to slot necessary. Previously with the Pentium Pro, Intel had combined processor and cache dies in the same Socket 8 package. These were connected by a full-speed bus, resulting in significant performance benefits. Unfortunately, this method required that the two components be bonded together early in the production process, before testing was possible. As a result, a single, tiny flaw in either die made it necessary to discard the entire assembly, causing low production yield and high cost. [2]

Intel subsequently designed a circuit board where the CPU and cache remained closely integrated, but were mounted on a printed circuit board, called a Single-Edged Contact Cartridge (SECC). The CPU and cache could be tested separately, before final assembly into a package, reducing cost and making the CPU more attractive to markets other than that of high-end servers. These cards could also be easily plugged into a Slot 1, thereby eliminating the chance for pins of a typical CPU to be bent or broken when installing in a socket.

 

Regardless of their reason, considering you can fit everything on a single die, or at least the CPU PCB package (look at Haswell ULV CPU's which has PCH on the package now), it'd be a bit silly to have a small CPU sitting vertically.

 

It's silly to have the bus interface spread around on a huge flat motherboard as well. Since the tech to drop all of the individual chips has been there, and been cost-efficient, for a long time. But it's kept that way anyway. On the pain of lawsuit.

I.e., the ION chipset died, and AMD's apus still have separate components on the die, even if several of the bus-interface functions (north-bridge, southbridge, etc.) are integrated on the die now. Never was a technical reason it happened that way.

The Tegra chip, for example, has all the components on the same die - but that can't happen with an x86 processor until Intel goes out of business. But it's technically possible to drop all of the motherboard chips and put them on one single die. It'd definitely mean more profits for people who manufacture laptops and pads to choose a solution like that. Would mean a smaller and more energy efficient design, etc.

But it won't happen with an x86 based chip, or a chip that aims to be a general purpose processing engine.

 

The other issue with these designs is that it tends to lengthen the electronic pathways. This along with other issues mentioned it also increases the number of contacts and possible failures. You had best forget using this type of tech on a notebook as well.................

 

Id love to see a slot like that with 2011 pins, it would look like a saturn rocket launch platform.

 

Yeah, lol. People are looking for sub one inch notebooks, this would mean six inch thick notebooks.

LOL yeah, it would be about a foot long too.

 

You know, they don't actually need to make chips with cm-long copper-contacts sticking out of it any more. The modular mainboard design isn't kept for technical reasons, at all. You will obviously have bleeding edge tech on the individual parts, with fantastically incremental increase in performance. To keep the production of these individual chips going. But the actual modular mainboard designs have been out of date, technically speaking, for a long while.

 

There needs to be some form of contact between the CPU and mainboard. Of course you can put the pins in the socket like Intel has done with desktop CPU's.

What is meant by "modular". PC's even laptops are still highly modular because parts are interchangeable. A range of CPU's can fit in a certain socket, as can wi-fi cards, SSD's/HDD's, RAM, etc.