Obviously, it isn’t processor speed or FSB.

alnielsen · Post by **alnielsen** » Thu Nov 06, 2003 11:44 am

As you can probably tell by the stats, I have started a new job and have been running SETI on a couple of computers. I found something I think is interesting.

IBM Netvista
Processor
Processor manufacturer: Intel
Processor (CPU)2: Intel Pentium 4
Processor internal clock speed2: 2.40GHz
Front Side Bus: 533MHz
512KB L2 Cache (for 2A GHz and Faster)
Processes a unit in 3.0-4.0 hrs.

IBM Thinkpad T40
Processor
BIOS type: Flash ROM
Processor manufacturer: Intel
Processor (CPU): Intel Pentium M processor
Processor internal clock speed2: 1.30GHz
Front Side Bus: 400MHz

1 MB On-Die Level 2 (L2) Cache
Processes a unit in 2.5-3.5 hrs.

The Pentium M processor, even tho it is almost ½ as fast and has a slower FSB, process the SETI unit faster. Must be the cache. Any comments?

Post by **Derek** » Thu Nov 06, 2003 11:59 am

I agree, it's probably the cache.

I'm not surprised to read this; I have heard that the Pentium M processor outperforms any other mobile chip out there by far.

HAL6000 · Post by **HAL6000** » Thu Nov 06, 2003 2:44 pm

The laptop I had was a 1Ghz P3 M with 512k, man that would smoke the 1Ghz coppermines

kuun · Post by **kuun** » Fri Nov 07, 2003 12:20 am

ok...

here's the thing

larger cache will dramatically cutdown on data lag...

you give the CPU larger cache.. it has a shorter wait time for data to be stored and then transfered for processing.. also it can store and transfer and proccess more at once with larger cache

kuun · Post by **kuun** » Fri Nov 07, 2003 12:21 am

ok...

here's the thing

larger cache will dramatically cutdown on data lag...

you give the CPU larger cache.. it has a shorter wait time for data to be stored and then transfered for processing.. also it can store and transfer and proccess more at once with larger cache

why do you tihnk XEONS being mostly slower than the top of the line pentiums will smoke a pentiums 2-3 times over

most new xeons have 2MB l2/l3 cache

cache is everything

estikid · Post by **estikid** » Sat Nov 08, 2003 11:53 am

Very true kuun, i remember reading an article about seti and cache usage, i think it may have been on this page - http://www.paradiseplace.org.uk/other/setiadvd.htm
I was wondering why my 1Ghz celeron was being outperformed by a p3 800mhz (on seti).

uallas5 · Post by **uallas5** » Thu Nov 13, 2003 10:31 am

Also. it's the greatly improved and shortened pipelines combined with better branch prediction of the Pentium M. In most head to head tests on compareable hardware, the M will smoke the desktop P4 on a purely Ghz standpoint.

Anand has a really good review http://www.anandtech.com/mobile/showdoc.html?i=1800&p=1 from shortly after the M had been released.

jives · Post by **jives** » Mon Dec 08, 2003 10:05 am

Part true part not.

The Anandtech article shows there is more to the Pentium M's gain than just seti.

Cache does help because yes my Xeon 450 w/1M out pace my PIII 600s w/512k, 750s w/256k and 850s w/256k. My Alpha EV6 500 w/4M can out my pace PIII 933 w/256k and comes within a few minutes of my Celeron 1.4G w/256k.

But it isn’t everything since I have PIII 1.2G w/256k and Athlon MP 1.2G w/384k (I think?) which are faster than the Alpha and Xeon.

So upping the CPU speed will gain you some, upping the FSB will get you some as well and upping the cache will speed it up. But as the CPU gets faster cache increases will grow in importance, the faster the CPU the more it is about the cache.