Hyper Threading vs. Dual Core 2

[snowcold]

I think I know the difference...HT is tricking the apps in thinking there are 2 CPUs where DualCore is actually 2 integrated CPUs....
Anyways, I'm looking into purchasing a new CPU and have found the Intel Pentium D 805 Smithfield..this has a Dual core but no HT for 95$.

AMD has a dual core with HT for 150$...would like to save the money to use it elsewhere....


Is it correct for me to think that the DualCore over the HT would be way to go?

Thanks,

 

[paparazi]

I think the best way of deciding which is best for you is to try out this CPU analysis tool on toms.
This is a useful tool because it compares CPU's in many different benchmarks and software enviroments and it will tell you how each particular CPU and platform performs with the applications that you most commonly use.

http://www.tomshardware.co.uk/cpu/charts.html

Martin

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Participate and help others.

 

[kmcferrin]

This can get somewhat complicated, but there are some things about HT to keep in mind. First and foremost, the acronym HT means different things for different vendors.

For Intel, it means "Hypthreading" (also called SMT or "Simultaneous Multi-Threading), which is a way of being able to execute two non-dependent instructions simultaneously in order to get a performance increase. In any application that runs faster with "Hyperthreading" than without, it will probably run even faster on a dual core or dual CPU system. AMD doesn't never produced "Hyperthreading" CPUs, based on the belief that the performance benefit would be negligible and that they would be producing true dual core CPUs soon enough.

AMD does not have any CPUs that support "Hyperthreading". To AMD, HT means "Hypertransport", which is a high-speed direct-connect interface that is used to connect CPUs to other system components (like CPU <-> chipset southbridge chip). Hyperthreading and Hypertransport are not related in any way.

Now as regards hyperthreading + dual core, only a very limited number of CPUs were produced by Intel that supported both, and I believe that they were all Extreme Edition pentium CPUs (though not all EE's were dual core and HT).

If you heart is set on dual core, but your budget is entry level, the Athlon 64 X2 3800+ (which I believe was the $150 CPU) will run circles around the Pentium D 805, and most of the rest of the Pentium D line. If you spend a little more money you can get a Core 2 Duo for $185, which should be a fair bit faster than the X2 3800+. But check Tom's site as paparazi suggested if you want the low-down on all of the possible permutations.

 

[skiflyer]

Don't even worry about HT as in HyperThreading... if you can get your hands on a dual core do, don't let HyperThreading hold you back.

HyperTransport is pretty freaking cool, but unless you're doing some serious server work don't stress... right now Intel makes the best dual cores for the money (this coming from a an AMD 4200+ Dual cores system right now... but I bought before the Intel release)

Of course... quad cores are only two quarters away!

 

[Sympology]

With HyperTransport, there are lot of things on the horizion, Physics cards, co Processors etc.
Also I can see AMD pulling on the teaming with IBM on supercomputing a big benifit, cell chips anyone?

But I guess that's another thread.

Only the truly stupid believe they know everything.
Stu.. 2004

 

[kmcferrin]

With HyperTransport, there are lot of things on the horizion, Physics cards, co Processors etc.
Also I can see AMD pulling on the teaming with IBM on supercomputing a big benifit, cell chips anyone?

They already did. IBM recently announced a supercomputer that had 16000 Opteron chips and 16000 Cell processors combined for Los Alamos. I don't think that they're using Hypertransport for the interconnects between the Cell and Opteron chips though, since they would be isolated in separate boxes.

But Hypertransport does make an interesting option when you are running true SMP hardware (especially in a multi-core package).

 

[skiflyer]

HyperTransport is what *should* give AMD the advantage on the 4x4 boxes... but so little code is really designed to take advantage of SMP (another reason HyperThreading has been lackluster) that who knows what us average home users will see.

The dual core is such a boon because it increases the responsiveness of the desktop during busy system times... but the quad core isn't going to advance that much.

As per the usual, interesting times in the chip development world.

 

[cdogg]

skiflyer,
But, it is important to note that most of the processors sold today are dual-core. Within a short amount of time, perhaps 2-3 years, you will start to see quite a few popular software titles available today modified to take advantage of SMP. Even though there are some apps like that today (Adobe products like Premiere, for example), there will be many more in the near future. SMP is clearly the pathway of the future, and it is way too early to count out the effectiveness of having even more cores on one die, such as 4, 6 or 8.


snowcold,
All Pentium D processors do not have Hyperthreading turned on. Only the Pentium EE (Extreme Edition) have it. Do not confuse this with Pentium 4 EE, which is a single-core CPU.

With that said, Hyperthreading has never been that much of a factor. Here's some hard, concrete evidence of Hyperthreading in action instead of just feeding you theory. I've been pointing people to the interactive CPU charts at Tom's Hardware for a while now. In the following link, you will see the Pentium D 840 Smithfield compared to a Pentium EE 840 Smithfield. I picked the Adobe Premiere and a gaming benchmark:

http://www.tomshardware.co.uk/cpu/charts.html?modelx=33&model1=445&model2=446&chart=185

http://www.tomshardware.co.uk/cpu/charts.html?modelx=33&model1=445&model2=446&chart=165

Besides Hyperthreading, these CPUs are identical. As you can see, Hyperthreading gives about 15% and 11% boost in performance respectively. In my opinion, that's great but it hardly justifies the price difference.

~cdogg
"Insanity: doing the same thing over and over again and expecting different results." - Albert Einstein
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[cdogg]

Forgot to mention that Hyperthreading has been dropped from newer Intel CPUs such as the Conroe, and all new CPU cores in the near future. I suppose it has been dubbed "energy-inefficient"...

http://en.wikipedia.org/wiki/Hyperthreading

~cdogg
"Insanity: doing the same thing over and over again and expecting different results." - Albert Einstein
[tab][navy]For general rules and guidelines to get better answers, click here:[/navy] faq219-2884