why there no dual CPU 939 boards?

[Dr.Mhz]

anyone know why there no dual 939 boards?

so u could have 2 x Amd 64bit cpu or even 2 X Amd 64 X2 in it.
I know thats some say that only the Opteron is suppose to be Dual compatible
but if theres dual core 939 cpu ,i dont why those cpu would nt be dual compatible?
Unless amd just does not want this to happen,,,,

Any other theories out there?

thk

[Crashman]

AMD doesn't want it to happen. They charge more for Opterons because they can. Their following Intel's example, the Xeons use the same cores as P4 desktop CPU's, but require a different socket.

Intel support dual desktop processors until the last of Socket 370, AMD supported it through Socket 462.

In spite of AMD's good core technology, they follow Intel on much of this stuff. Intel went to Slot-1, AMD later went to Slot-A. Intel moved to Socket 370, AMD later moved to Socket A (socket 462). Intel moved to eliminate dual desktop CPU sockets, AMD made the move a couple years later.

[Peter M]

It's not about pure marketing. Opterons are actually different from Athlons, in that they have not one HyperTransport link but three. Series 200 and 800 Opterons can use one/two of them for CPU interconnect. Besides that, the Opteron pinout is optimized for server-grade "ECC registered" DIMMs.

And here's the answer to the original question: There aren't any because the socket-939 processors lack the interconnect between CPUs.

Socket-462 Athlons in turn didn't contain _any_ technology for dual processing. This was totally chipset driven, in that the AMD762 north bridge had twin independent (!) CPU busses.

[AllGamer]

Technically in Architecture they are just slightly different, but the same in the end, those boards runing Opteron CPU can also run Athlon CPUs, it's done a lot cost less and goes faster.

but yes it's pure marketing, they just don;t want people abandoning the Opteron, and go all cheap using regular Athlons CPUs :D

[Peter M]

No the Opteron boards can't run Athlons. As has been explained above, they are substantially different in what I/O they offer. Socket pinout as it happens is also substantially different, not just one more pin.

[AllGamer]

it works, many people are doing that here.

Now obviously it will not work for the 64bit version of Athlons, but it does work for the normal ones.

The ASUS dual CPU board for "opteron" is the best seller

[Peter M]

Don't try to cover up bullsh*t with even more hilarious bullsh*t.

"Normal" 32-bit Athlons use an even more entirely different socket, socket-A. Yes, on this old architecture, Athlon-MP and Athlon-XP are using the same socket and same pinout.

However, there still is NO Athlon that would fit an Opteron board, not 32- and not 64-bit.

[Crashman]

Hey Peter, I thought the first Athlon FX processors were Socket 940.

[Peter M]

Well yes. These technically were Opteron 100 series CPUs - registered DIMMs required, three HT links, none of them suitable for inter-CPU linking ("coherent"). The difference was and is that FX series CPUs aren't multiplier locked.

Still, you can't make a dual-CPU system from those either.

[chubtub]

Is this one?
http://www.anandtech.com/mb/showdoc.aspx?i=2524

[Peter M]

Hello? Haven't we just explained that dual S939 processors is TECHNICALLY IMPOSSIBLE? And have you even looked at the article? 'Cause if you had, you'd have noticed that it has ONE processor socket.

[chubtub]

Nope didn't read it all just scanned it fast. And just shot the link out fast, thought it was relavant. :eek:

[AllGamer]

of course it does work, look

http://usa.asus.com/products/mb/socketa/a7m266-d/overview.htm#

everyone has been using and doing it for ages :rolleyes:

[RamonGTP]

of course it does work, look

http://usa.asus.com/products/mb/socketa/a7m266-d/overview.htm#

everyone has been using and doing it for ages :rolleyes:

Thats not an opteron board guy... You said opteron boards can run regular athlon cpu's which is infact false. The only other cpu that you can run on an opteron board is the very first generation of the FX processor which was Socket 940 and you can't even get those anymore since they've moved to Socket 939.

[AllGamer]

isn't the MP the Opteron? :confused:

[RamonGTP]

no... MP is the the multi processor version of the AthlonXP which is part of the K7 family. Opteron is a 64bit processor designed for servers and can be used in multi processor environments. As Peter M said, has 3 HT busses versus the 1 for a regular Athlon64 which is why it can be used it multi processor configurations and which is also why its not possible for an Athlon64 to be used in multi processor configs. Opteron also uses ECC Registered ram which is why its a Socket 940 CPU instead of a Socket 939

[Peter M]

Oh no it isn't. That's why it's usually recommended to know what you're talking about before talking.

The Athlon-MP was the dual processor version of the OLD (32-bit socket-A) Athlon architecture.

[sm8000]

Opteron also uses ECC Registered ram which is why its a Socket 940 CPU instead of a Socket 939

Opteron requires that the RAM be registered. Doesn't necessarily mean it has to be ECC (the two are mutually exclusive).

[Someone Stupid]

No

The rest I posted isn't even needed this was pounced on so fast. Cut the ether out.

Opterons only just stopped requiring ECC, so that is forgivable on Ramons part. The savings you have on the ram are offset by the added cost of the chip. A rather odd move there, but one with some logic, albeit only some IMO.

[sm8000]

Ether is a hell of a drug, isn't it? :r


Pounced on so fast? You're a little late to the party there, your car break down or something? :D Anyway when did Opterons ever absolutely require ECC? Don't get me wrong, it's not like I've been keeping close track ;)


Anyway, I think all SysOpt users with Opteron systems should get together and call themselves SysOpterons :x


Like I said, ether's a hell of a drug :p

[Peter M]

No

The rest I posted isn't even needed this was pounced on so fast. Cut the ether out.

Opterons only just stopped requiring ECC, so that is forgivable on Ramons part. The savings you have on the ram are offset by the added cost of the chip. A rather odd move there, but one with some logic, albeit only some IMO.

Opterons never required ECC; they require _registered_ DIMMs - with or without ECC.

By popular demand (read: SGI's request) there now are additional "Opteron-100" series branded processors for socket-939 which again can do ECC but don't have to, and require _unbuffered_ DIMMs. These are essentially Athlon-64 processors with a different badge on - one HT link, no multiprocessing, unbuffered DIMMs.

[Dr.Mhz]

thk guys,, that is great input

Yeah I think there is no 939 dual ,just to stop small buiness to go cheap and force them to go oteron.

All the other dual are either opteron 940 or socket A..

I just wish there was a 939 dual ,,, so I could have quatro core before its time,,,lol

thk guys

[fryincpus]

Hopefully, we won't be having the same discussion again in the next few years when quad cores come out. ;)

[Peter M]

Dr. Mhz, you need to realize that the price delta from Athlons to Opterons is exactly because of the missing features. You gets what you pays for. After all, socket-939 originally was a cost reduction downstrip from socket-940 to begin with. Remember?

[Dr.Mhz]

I know and thk Peter M ,, I gues im in wishful thinking mode.

I probably feel better when I buy that dual core,,Im just wondering ,while waiting for
a ULI 1695 board to go retail(in canada).

I dont know if we'll have that discusion again,,but i'll be thinking about it.
LOL