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Checking for Hyper-threading and SSE4

Posted: Tue Jan 19, 2010 4:15 am
by hjazz
Hi all,

How do I check if my processor supports hyper-threading and SSE4?

I have an Intel Xeon E5405 @ 2.00GHz running Linux, and the flags column in /proc/cpuinfo displays ht and sse2. However, the Intel website (http://ark.intel.com/Product.aspx?id=33 ... LAP2,SLBBP) says that HT is not
supported by Intel Xeon E5405.

Also, is SSE4 only supported by Core i7?

Thank you.

Regards,
Rayne

Re: Checking for Hyper-threading and SSE4

Posted: Tue Jan 19, 2010 6:13 am
by shamrok3
Try CPU-Z. It should list all of the features of your CPU.

Re: Checking for Hyper-threading and SSE4

Posted: Tue Jan 19, 2010 6:20 am
by DMB2000uk
I'd be more tempted to believe the intel website for specs. I'm pretty sure it's only the nehelm (and old P4 based) CPUs that have HT support.

Wikipedia lists your processor as supporting SSE4.1.

Dan

Re: Checking for Hyper-threading and SSE4

Posted: Tue Jan 19, 2010 1:27 pm
by kenc51
That CPU supports SSE4 & SSE4.1 (and every version before that)
SSE4.2 came out afterwards and is only supported on i7 series chips.
The CPU does not support hyperthreading either, has 4 cores and support for 4 threads.

AMD only supports SSE4 and not 4.1 or above.

The difference between SSE4.1 & 4.2 is minimal at best. (Only 7 new instructions added, and none of them of any value to the average consumer)

More info from Intel here
http://softwarecommunity.intel.com/isn/ ... erence.pdf

Re: Checking for Hyper-threading and SSE4

Posted: Tue Jan 19, 2010 8:12 pm
by hjazz
Thanks for all the replies!
DMB2000uk wrote:I'd be more tempted to believe the intel website for specs. I'm pretty sure it's only the nehelm (and old P4 based) CPUs that have HT support.

Wikipedia lists your processor as supporting SSE4.1.

Dan
What about Intel Xeon X5570? The Intel site says it supports HT. But this is where I'm confused. I thought HT was discontinued for a while and then only recently brought back in Core i7. Although Xeon X5570 is launched after Core i7, so maybe HT is supported in all processors after Core i7?

If X5570 does support both HT and SSE4, would its performance vary much from Core i7, when everything else is kept the same?

Re: Checking for Hyper-threading and SSE4

Posted: Wed Jan 20, 2010 3:38 am
by DMB2000uk
It's easier to think about it in terms of the chip architecture rather than i7 vs Xeon (As there are lots of different Xeon CPU architectures over the years). The new chips that are built with hyperthreading etc are called Nehelam, and they use the 'new' socket 1366.

So the easiest way to work out if it supports hyperthreading is to see if it is using the new socket 1366, or alternatively, if it uses QPI (quick path interconnect) instead of FSB, it's also one of the new i7 (nehalem) based Xeons.

Dan