Intel Dual Core Xeon Benchmarked

An anonymous reader writes "A few weeks back, Intel launched a new dual core chip with little applause. It appears we know now why, as the chip has been benchmarked by the chaps at GamePC. In tests against the dual core AMD Opteron processor, Intel's new chip gets thoroughly thrashed, losing out in terms of raw performance while eating a lot more power. "

Comments

AMD's dual cores are great

[jarich]

I just bought my wife a dual core (3800 model) and it's just as responsive as my dual Opteron. I'm seriously considering selling my dual CPU box and getting a dual core myself just to have fewer fans in the box and generate less heat.

I had been considering an Intel dual core but it sounds like I need to aim for an AMD instead.

Re:AMD's dual cores are great

[Jherek Carnelian]

They aren't real dual-cores hence the abysmal performance

No, they are honest-to-goodness real dual cores. Two fully functional cpus in a single socket.

The problem is that the socket only has enough memory bandwidth for one cpu's worth of work. So, even if you double the number of cpus, you still can't shovel the data in and out fast enough to keep up with the work being done. Thus one of the two cores is almost always stalled out waiting on memory.

The AMD chips have got more memory bandwidth, so they can keep both cpus fed with data reasonably well.

Coral cache link

[Freggy]

http://www.gamepc.com.nyud.net:8090/labs/view_cont ent.asp?id=paxville&page=1

Seems it's slashdotted already after 8 posts. Finally when will all slashdot-links be coralized automatically?

Re:Yet strangly...

[PygmySurfer]

Intel's sales will again beat AMD's by several fold. The reason seems to be that most PC and server purchases are not intended for games, beyond Solitare of course, and people prefer the reliability, power savings and lower temperatures of the Intel chips.

Did you miss the part where they said this chip consumes more power and runs hotter than Opterons?

Hyper Threading

[DrYak]

Additionnally to what other have said, I may add :
- HyperThreading is Intel's name for Simultaneous Multithreading.

Basically, a CPU isn't always using 100% of all its function.
The CPU may be waiting for something in the cache.
Or the application is maybe using only a small portion of the CPU.
In other words, the CPU waste its time sitting and doing nothing.

If you manage to use those unused ressource, you can squeeze more performance out of your CPU.
Before Simultaneous Multithreading, the only way to do so is "Out-of-Order" execution.
- In plain english : maybe some of the next steps of the programm don't need to wait the curent stuff to finish, and we may already fill unused parts of the CPU with these instruction.

With Simultaneous Multithreading, this time, you're trying to find something for your CPU to do from *another program*. This program must wait for something from the cache ? Let's run another in the meantime.

----

Alternate explanation :
Multi tasking/ Multi Multithreading is when several program share the same CPU by quickly alternating between them.
Simultaneous Multithreading is when 2 program run at the same time so less parts of the CPU are just sitting unused.

Just specced out an AMD system for MHD modeling

[Dr. Zowie]

Running a Xeon dual-core is like mounting a Chevy big-block engine under a VW carburetor. The memory access just isn't there. Most of my stuff (modeling the solar corona) is RAM-bound anyway, so there's no win to be had at all by running the dual Intel cores. The Opterons have better RAM latency, which is a win -- but, more importantly, the two cores communicate cache-to-cache at the CPU clock speed, so dual-threaded processes run amazingly fast. If they're sharing memory, you effectively double the L2 cache size of both cores, which is a big win all around.

So, er, Xeon is teh 5uk and Opteron Pwns.