Opteron vs. 64 vs X2 question

[Spase]

I realise that the Opterons are made for servers, but from what I have read, they work pretty similarly to the 64's and X2's. I was just wondering what everyone thought of them.

[Belisarius]

From what I understand, and Fozz can correct me here is this:

Athlon 64 have a 64 bit instruction set so they can process 64 bits of information at a time, a step up from the old standard of 32 bits.

X2 is two processors on one chip, ie dual core.

Opteron is the server/workstation version of the above. Basically when a chip batch is run, they test a sample and determine how well the chip was made. For example if they are trying to make Athlon XP 4400s and a certain percentage of that batch is much better than the others, those they make Opteron 175s 939 pins.

I would imagine that if they made Opteron 940 pins and they didn't make the grade, they'd just toss em.

[Liin]

From what I have read about the Opterons vs. the A64 and athlon x2 are that the Opterons have more headroom if you are going to overclock and will run cooler doing so. They are for servers mainly, but they produce them in socket 939 so they can be used in a regular socket 939 board. You may have to flash your bios to get the board to recognise them as well. Also if you do not use them in a server recognised board you void the warranty but most who have bought them for desktop use overclock too so it really matters not to them if they have a warranty.

As I am getting ready for my newest build, I will be looking at both the x2 and opteron 170-175 pricing as I near the time when I am ready to put it all together.

[Fozzik]

Bel and Liin pretty much covered it. The architecture is exactly the same between Athlon 64s and 939-pin Opterons. The only difference is perhaps the amount of testing and validation that they do...so the reason some Opteron chips might overclock better is probably because they are the most stable chips which AMD produced, and came through all the testing to become server/workstation chips.

Not to say that Athlon 64s are less than stable. They are extremely stable in my experience, at their rated speeds and with a solid motherboard... Opterons are probably just tested using very different workloads, since their intended purpose is different.

An Athlon 64 and Opteron which are both running at the same clock speed, have the same cache, use the same socket, and are the same chip revision... are the exact same chip.

[Spase]

Alright. Thanks for the info.

One other slightly related question: How do you tell the revision of a chip when buying it? and how do you know which is the newer revision?

[Slide]

I've heard people hav had really good results overclocking the Socket 939 Opterons - ie being bale to clock them to FX-57 speeds. They are a great choice if you're not scared of o/cing, and want a great performing single cpu at a great pricepoint.

[Fozzik]

I'm pretty sure AMD is sticking to a basic letter system for their core revisions... as in A, B, C... etc.

The current "newest" revision is the E, and F is coming this year sometime.

The revision is specified in the number code on each processor, and should also be mentioned somewhere in the information on whatever site you are buying it from. There is info on AMD's website about how to break down the part numbers. I'll see if I can find the page when I get home.

[Breogan]

Opteron are practically the same as AMD64 with 1Mb cache, but some people are finding more luck overclocking the Opterons. They got their fame because the first batch was supposedly made from renamed FX processors.

If you want to squeeze the last drop out of your CPU overclocking it, go for an Opteron. Otherwise it might not be worth to pay the plus.

Opteron part numbers:

Single core (all the socket 939 single core Opterons are rev. E4)

Opteron 154 - OSA154DAA5BN - 2.8Ghz/1Mb
Opteron 152 - OSA152DAA5BN - 2.6Ghz/1Mb
Opteron 150 - OSA150DAA5BN - 2.4Ghz/1Mb (AMD64 4000+)
Opteron 148 - OSA148DAA5BN - 2.2Ghz/1Mb (AMD64 3700+)
Opteron 146 - OSA146DAA5BN - 2.0Ghz/1Mb
Opteron 144 - OSA144DAA5BN - 1.8Ghz/1Mb

Dual core (all the socket 939 dual core Opterons are rev. E6)

Opteron 180 - OSA180DAA6CD - 2.4Ghz/2Mb (AMD64 X2 4800+)
Opteron 175 - OSA175DAA6CD - 2.2Ghz/2Mb (AMD64 X2 4400+)
Opteron 170 - OSA170DAA6CD - 2.0Ghz/2Mb (AMD64 X2 4000+)
Opteron 165 - OSA165DAA6CD - 1.8Ghz/2Mb

NOTE: The last 2 characters are the core revision. The boxed version of the procesor is called using the OSA### convention and adding the revision code and BOX at the end. Example: OSA152BNBOX or OSA175CDBOX. Also, AMD64 X2 4000+ doesn't exist but this processor would be the equivalent if it were to exist.