SPCR

Someone over at xtremesystems forums posted a CBI (Central Brain Identifier) screenshot of the upcoming dual core Opteron. Link

It is the Opteron 275 at 2.2 GHz and only 1.2V. He claims it dissipates 68W. Wonderful numbers, this means 2.4G dual core would be possible easily, from a thermal output viewpoint. 2.2 GHz corresponds to 3500+, so call it a 3.4GHz Presscott. Intel is bringing out dual cores up to 3.2GHz, and as far as I know, has no short term plans to increase clockspeed on dualcores. Based on this info, I think dual core AMD procs are looking reallly really good. My only question is what are the prices going to be???

Oh, one last thing. At the bottom of the screenshot, see the YES next to Hyper-Threading? ?????? Are we in for a surprise of some sort?

If it really is as good as it sounds, I think AMD are going to be a silencer's favourite for a while. But how much will it cost?

cansan wrote:Oh, one last thing. At the bottom of the screenshot, see the YES next to Hyper-Threading? ?????? Are we in for a surprise of some sort?

I read an explanation for this in dutch yesterday. Most of it went over my head, but the bottom line was that the AMD chip doesn't have Hyper-Threading. By setting this bit in some identifier on the chip, the AMD dual core chips can benefit from some software/compiler optimisations designed for the Intel chips that do have Hyper-Threading.

Tibors wrote:By setting this bit in some identifier on the chip, the AMD dual core chips can benefit from some software/compiler optimisations designed for the Intel chips that do have Hyper-Threading.

I'm confused. In Hyper-Threading the OS sees two virtual CPUs. Does this help for SMP aware applications only (multi threaded), or is it somehow useful for single threaded apps as well?

So (I'm just speculating) if hyper-threading helps in single threaded apps(?) and if AMD has figured out a way to make its two physical cores look like virtual ones, can we possibly see better single threaded application performance with dual cores as well? (I am aware that I am being wildly optimistic here, but if its true, )

That would be a pretty amazing system. My guess is you are going to have to get your checkbook out for it though. $440 for the current 2.2ghz Opteron plus an expensive 940 MB plus registered RAM.

Overclockers.com is suggesting it will be a while before we get desktop dual core from AMD.

Chris

Where did you get this price info? 440$ for 2.2, ouch! I wonder how will the desktop dual cores be priced? The same or lower?

I just read through some hyper-threading benchmarks, single thread performance is not affected. I'm still confused though. The applications that can and do operate with multiple threads will see 2 processors. It shouldn't matter it they see 2 virtual or real CPUs. Does it?

AFAIK hyperthreading lets two threads use parts of the core simultaneously (but not the same part). As far as the application is concerned dual-core should be no different to an HT processor; it leaves Windows to schedule the threads. But I'm not 100% on this.

All of this rather begs the question: Why did AMD even bother to make it look like a HT enabled processor?

To spark debate at the cost of flipping a bit.

(well, why not? If they can jump on the HT bandwagon...)

StarfishChris wrote:AFAIK hyperthreading lets two threads use parts of the core simultaneously (but not the same part). As far as the application is concerned dual-core should be no different to an HT processor; it leaves Windows to schedule the threads. But I'm not 100% on this.

This is correct. Intels HT is basically a standard CPU that will let threads use different parts of the CPU at the same time. So for example one thread might be using the integer unit while a second thread is using the floating point unit. These threads share the same registers, instruction decoder and cache. So in some cases HT will run somewhat faster than the same speed P4 without HT. But some things will run slower because the threads will end up fighting each other over things like the registers which on x86 processors are limited even for a single thread.

Dual core is two full processors on the same chip. So the only thing they share is the memory bus and and in the caase of the amd64 the memory controller. Each core has it own logic unit, integer unit, FPU, instruction decoder and cache. This means that a dual core amd64 has 4 times as many registers and two times as many of everything else than a P4 HT processor. The only possible place for contention is the memory controllor/memory bus.

So why would AMD set the HT bit? So that 32 bit code compiled with optimizations for the P4 HT will use those same optimization when running on a dual core AMD. It would appear that the dual core AMDs benifit from at least some of the same optimizations. Also I suspect that Windows would see one of these chips as a single CPU unless the HT bit is set and would not dispatch more than one thread at a time (Windows would only use one core).

StarfishChris wrote:If it really is as good as it sounds, I think AMD are going to be a silencer's favourite for a while. But how much will it cost?

According to Matbe.com, here are the expected prices:

• Opteron 265 : 851€
• Opteron 275 : 1299€
• Opteton 865 : 1514€
• Opteron 875 : 2649€

From BeHardware:

Next April 21 for the second birthday of the Opteron, AMD will release dual cores processors for servers. The Opteron 265 and 865 will be clocked at 1.8 GHz, 2.0 GHz for the 270/870 and 2.2 GHz for the 275/875 versions. The Opteron 265 and 275 will cost $851 and $1299, and the 865 and 875 $1514 and $2649. The dual core Opteron 265 clocked at 1.8 GHz will be more expensive than two Opteron 244 1.8 GHz ($209 reach) for example and it is the same thing for the rest of the range.

Now we have to hope that the pricing policy will be different for the Athlon 64 dual core range expected in Q3, and that AMD only takes advantage of the dual core compared to the single core in terms of processor density per rack to increase the bill.

Opteron Dual Core Power consumption:

x80 / 2.4 GHz / 1.35V / 80A / 95 Watts TDP
x75 / 2.2 GHz / 1.35V / 80A / 95 Watts TDP
x75 / 2.2 GHz / 1.15V / 48A / 55 Watts TDP
x70 / 2.0 GHz / 1.15V / 48A / 55 Watts TDP
x60 / 1.6 GHz / 1.10V / 30A / 30 Watts TDP



There's a test of the Dual Core Opteron at HKEPC Hardware.

Looking at those prices and the overclockers article, I guess that AMD is not going to be making many dual cores for a while. Hopefully by the end of the year we'll see something affordable (and on s939).

According to DigiTimes Mobos, Intel also loves huge prices:

The dual-core 840 CPU that supports Hyper-Threading will be priced at US$999, said the makers, adding that quotes for the 955X chipset should be US$50. Motherboards using Intel’s 955X chipsets will cost about US$200 per board, the makers estimated.

According to this news on matbe.com, these are the official prices and models:

Athlon 64 X2 4200+ : 537$
Athlon 64 X2 4400+ : 581$
Athlon 64 X2 4600+ : 803$
Athlon 64 X2 4800+ : 1001$

Opteron 265 : 851$
Opteron 275 : 1299$
Opteron 865 : 1514$
Opteron 875 : 2649$

Yeah, the prices really hurt. But the performance is there:
Anandtech Review
TechReport Review