Dual CPU machines possible?

[NAC]

A decade ago or so, dual CPU motherboards were popular, often with overclocked Celeron's. It was the cheapest way to get processing power. I don't recall specifics, but Intel didn't prevent the practice for years.

Now with CPUs like the i5 2500k going for $140, and processing power not increasing (as) much over the last few generations, I'd love to be able to setup a dual CPU machine. Eight cores might be overkill for games, but I'm sure that photo & video editing, rendering, etc. would benefit.

So, is it possible today, or only with super expensive server hardware? Is there a technical reason why it has to be much more expensive? Any predictions for the near future? If Intel sales are languishing, I'm sure some hobbyists will decide to spend money again if we can get twice the processing power for not a huge amount of money. I wouldn't think that 6 core CPU sales would suffer much, because if a person spends $1k to get the best, he will probably spend $2k to get two of the best.

 

[tweakboy]

YES its called

Xeon Server CPU and Xeon dual socket mobo. Put two 8 core chips,. each @ 1.4k lol

 

[Eureka]

They still have them with dual 2011s. I don't think I've ever seen a dual 1155/6 system yet.

 

[Ken g6]

1155 doesn't have the wiring to do dual sockets. 2011 does, but only with Xeons. There were LGA1156 dual socket mobos, though.

If you go AMD, you can get 8 "cores" in one chip, and I've heard of up to four sockets on one mobo!

 

[NTMBK]

Only with expensive server/workstation chips, like the Xeon-EPs.

Modern CPUs have things like the memory controller integrated, so the old methods of connecting multiple CPUs (sharing an FSB) no longer work. Modern multi-socket setups have asymmetrical memory layouts (NUMA) where each socket has banks of memory attached to it, and special links between the sockets. Intel uses QPI, AMD has Hypertransport.

This technique is far better than the old way (scales better to multiple sockets, higher performance) but requires support to be built into both the platform and the processor. Consumer chips don't have this.

 

[Denithor]

http://www.newegg.com/Product/Produc...=1&srchInDesc=

Dual 2011 boards - start around $365. Plus the cost of two Xeon chips.

So, yeah, they're available, but pricey.

I suppose if your work is multi-threaded enough these could be justified...

 

[Charles Kozierok]

It's also a deliberate market segmentation strategy. Hardware companies decide that "regular users don't need multiprocessing", target it only at servers, and then they can justify jacking up the prices.

 

[cytg111]

...I don't recall specifics, but Intel didn't prevent the practice for years. .

- Arh, not quite true, I had a friend back in the uni days that did the dual celeron trick .. you had to *drill* actual holes through the damned chips to make em work in dual mode. But it worked!! dual celeron 300@450MHz .. screaming beast (and faster at many things than equal regular P2's due to the full speed on die cache.)

 

[ShintaiDK]

1155 doesn't have the wiring to do dual sockets. 2011 does, but only with Xeons. There were LGA1156 dual socket mobos, though.!

Got a link for that?

Dualsocket aint possible on LGA11xx due to there is no QPI links to connect the CPUs. The only external interfaces on LGA11xx is 20 lanes of PCIe, 16 for GFX and 4 for the PCH.

 

[IntelEnthusiast]

We didn't release any socket 1156 processors that would work in a dual socket configuration. While we did release some some Intel® Xeon® 3000 sequence that were designed for a single socket boards (entry level server) haven't heard of any of them that would work in a multi processor set up.

 

[SPBHM]

years ago I think it was a lot easier, like Socket A, or 370.
but even Socket 479 (mobile) received some dual CPU boards,

now with the level of integration, if they didn't design the platform for dual CPUs, it's probably "impossible"...

So... you need some Xeon 2011 for that.

 

[ShintaiDK]

years ago I think it was a lot easier, like Socket A, or 370.
but even Socket 479 (mobile) received some dual CPU boards,

now with the level of integration, if they didn't design the platform for dual CPUs, it's probably "impossible"...

So... you need some Xeon 2011 for that.

It was up to LGA775. Since there was an FSB that could be shared. But with the death of the FSB, QPI was required instead. And LGA11xx doesnt have any of those externally.

 

[Ken g6]

Got a link for that?

Dualsocket aint possible on LGA11xx due to there is no QPI links to connect the CPUs. The only external interfaces on LGA11xx is 20 lanes of PCIe, 16 for GFX and 4 for the PCH.

I could swear I'd seen one. I must be thinking of the hex-core CPUs instead.

 

[moonbogg]

I thought EVGA had a dual socket 2011 board that supported two 3930k's.

 

[meloz]

It's also a deliberate market segmentation strategy. Hardware companies decide that "regular users don't need multiprocessing"

You are somehow equating multiprocessing with multithreading.

No, their thinking is that regular people do not need excessive multithreading. Which is correct approach, since a single-socket SB-E can thrash dual-socket systems from a few years ago (because over the years both the number of cores-per-socket and IPC have increased), and in typical desktop usage most people do not peg all their CPU cores at 100%.

The whole purpose of dual and quad socket multiprocessing systems is to get more cores / threads in a system. In datacentre and certain niche workstation segments that is still valuable, and will remain so for a long time.

But on typical desktop most people simply do not have that kind of usage requirement.

 

[ViRGE]

I thought EVGA had a dual socket 2011 board that supported two 3930k's.

The Classified SR-X only supports Xeons. Intel locked out the Core i7 (SNB-E) processors from multisocket operation.

 

[mv2devnull]

It was the cheapest way to get processing power.

Eight cores might be overkill for games, but I'm sure that photo & video editing, rendering, etc. would benefit.

"Cheapest way" for those just now is probably a graphics card or two and applications that are able to use GPGPU rather than plain CPU.

There are still single-threaded applications that do not benefit from additional cores. Same was much more true last century, but the leap from one core to two made significant difference nevertheless.

 

[Charles Kozierok]

You are somehow equating multiprocessing with multithreading.

Sorry, I was using the pre-multicore, pre-HT definition, which meant multiple CPUs.

 

[tynopik]

cheapest way (not counting used) is probably with some opterons ($290 + 2*$135= $560)

on the intel side, probably socket 1356 with xeon E5-24xx series cpus ($270 + 2*$220 = $710)

 

[2is]

Unless you make your living off of video/photo editing, spending a small fortune on a dual socket xeon system over an i7 1155 system is probably not worth it, unless it will allow you to either:

A) Get a lot more work done in the same amount of time resulting in more income

or

B) Get the same amount of work done in less time giving you more leisure time

It's important to remember that a decade ago, we only had single core processors in the consumer space, so you had to go dual sockets if you wanted more processing power.

 

[Markfw]

OK, I don't see the problem here. If you need that much horsepower (I do), then $1200 for a motherboard and 2 processors is not out of line. Whats the beef here ? $1200 for 24 threads ?

 

[vladicaris]

that kind of motherboard is only for special machines..

 

[mv2devnull]

that kind of motherboard is only for special machines..

Depends on the viewpoint. If buying feature set X has became a standard procedure, then X is normal even if it would be special for someone else.

There is asymmetry though. Let say your normal PC is self-built. You don't consider both cheap HP Pavillion from supermarket and HP ProLiant DL900 similarly special, even though you are not likely to use either.

Then again, aren't most PC's purchased with some particular purpose in mind? That would make them all special.


There is a need for different horses. A single-threaded game is happy with single CPU, if you can clock it high. Multi-processing can be happy with cluster of 8 single-CPU nodes, but certain number crunching applications really do prefer a single computer with 8 10-core CPUs. Obviously, neither of the latter two is what you do at home.

 

[Charles Kozierok]

It's important to remember that a decade ago, we only had single core processors in the consumer space, so you had to go dual sockets if you wanted more processing power.

True, of course, but as I recall, it was quite a bit easier to go dual socket than it is now. You didn't need nearly as much specialized, expensive hardware.

 

[PlasmaBomb]

I thought EVGA had a dual socket 2011 board that supported two 3930k's.

The SR-X only supports dual xeons unless they have something else?