Opteron versus Athlon -- dual core

[Artic_Kid]

AnandTech has an article about using the new Opteron 165 dual core processor. Apparently this processor now (a) requires less cash, and (b) has more cache -- than the equivalent Athlon dual core processor. And this Opteron, they say, can be overclocked to an equal clock speed.

Sounds interesting.

• What are the pro's and cons of doing that?
  
• I hear Opterons and Athlons are essentially the same chip -- so what's the difference? (I presume there must be some difference, but it's unclear to me what it is.)
  
• Are the Opterons (socket 939) fully compatible with the usual socket 939 motherboards? (I presume the answer is yes.)

[NightshadowUK]

I'm also interested in this as I could get an Opteron 146 for roughly the same price as an Athlon 3200+.

But which to purchase?!

[oralpain]

S939 opterons are the exact same cores as San Diego and Toledo core Athlon 64s and Athlon 64Xs. They are just tested/binned better as they are intended for in workstations and servers.

An opteron 165 is better than an X2 3800+, if you have a good overclocking motherboard. It's cheaper, and potentially faster. It has double the cache and will on average OC just as much. The only downside is the 9 multiplier, which means to reach it's full potential you will need a motherbaord that will be stable at 300MHz plus reference clock. For the most part is most DFI boards, the newer ASUS SLI32x, and the better Abit NF4 boards, and a few Sapphire boards.

The S939 opteron 146 is a 2Ghz 1M L2 cache chip based on the san deigo core. If it's the same price as an A64 3200+, I would get the former, but I would not pay much extra for the opteron.

[Artic_Kid]

Thanks oralpain, that was helpful!

S939 opterons are the exact same cores as San Diego and Toledo core Athlon 64s and Athlon 64Xs. .... The only downside is the 9 multiplier, ...

So the processor cores are the same, but the there's something different about the multiplier -- so presumably there's a difference in their memory controllers??? Can you tell me more about the difference between Opterons and Athlons? Perhaps an online article that would explain it?

They are just tested/binned better as they are intended for in workstations and servers.

If the Opterons are "tested/binned better", I gather that would mean they perform closer to spec, and so would not overclock as well as a chip having looser testing/binning. Do I have that right?

[Applecrusher]

So the processor cores are the same, but the there's something different about the multiplier -- so presumably there's a difference in their memory controllers??? Can you tell me more about the difference between Opterons and Athlons? Perhaps an online article that would explain it?

The multiplier is what you multiply the FSB by, only the FX chips are upwards unlocked. This means that you can easily make the cpu go faster witohout stressing the memory.

If the Opterons are "tested/binned better", I gather that would mean they perform closer to spec, and so would not overclock as well as a chip having looser testing/binning. Do I have that right?

No, it means that they are tested and are guaranteed to run 100% stably all the time, they are the better chips.. they (by looking at the boards) also overclock much better

[oralpain]

If the Opterons are "tested/binned better", I gather that would mean they perform closer to spec, and so would not overclock as well as a chip having looser testing/binning. Do I have that right?

Technically you are right, but you are still wrong. "Better" binning would be more efficent and would run things more closer to their limits so they could sell the chip at the highest possible price.

However "better" binning in this case is making sure the chips will virtually never fail at there ratted speeds, so they are advertised (and set at stock) to run farther from the actual limits of the chip.

The idea is alwasy to get as close as you can without failure, but opterons absolutly must not fail, under industrial use. A64s...well it's ok if they don't work some of the time, under home use. The standards are different.

There is no difference in the way the cores are made.

They find out what some of the chips in a batch will do, then they assign them to the processors that match the tested capabilities best. People are gonna be sticking these opterons in hot, dusty, servers and running them at thier limits for years are a time, and they have to work flawlessly, so they are given a much larger margin than the desktop chips. Better quality control. That's why they tend to OC better.

Read up on how CPUs are made and tested that will give you more specifics. Even if it not about A64s or Opterons, or AMD chips, or it's 10 years old, the concept will still be valid.

[NightshadowUK]

What's the difference between a '1-way Opteron' and an 'Opteron UP'?