What's your per iteration time?

[Dresdenboy]

Originally Posted by xtreme2k

Dual Channel DDR2700 vs Single Channel PC133...

5.4GB/s of bandwidth vs 1.06GB/s of bandwidth.

Surely the PC133 system will have much more impact.

At http://www.anandtech.com/chipsets/sh...i=1731&p=6 you'll find some details about nForce2 IGP/discrete graphics and single/dual channel config. An intel IGP is mentioned in the text.

In 2D benchmarks the dual channel gives some 0.x to 2.x % performance increase over single channel - as expected. 3D stuff is much more bandwidth hungry but the 100-200 MB/s for average 2D display modes have little impact. But they are still too much for PC133 while being only a little overhead for 2xDDR2700. And the Athlon FSB can't even fetch that much (2.7 or 3.2GB/s in the latest models).

Matthias

[QuintLeo]

Originally Posted by hyh1048576

But on my PC,the next resolution larger is 1600*1200?!?!?!?!?!?!? ?

Oops - you're right.

I think it may depend on the video card, though - *thought* I was running 1600x1280, but turns out I'm running 1600x1200, but I distinctly remember it being 1600x1280 on the first machine I used that was capable of higher than 1280x1024 resolution.

<mock glares at NVidea, for depriving me of my rightfull extra 80 lines of resolution>

9-)

[patrik]

Originally Posted by eepiccolo

[...] You should be able to consult a motherboard manual to find out exactly how the integrated graphics work for that particular board.

Thanks! I had already planned spending my vacation this summer downloading manuals and choosing the best motherboard for a small PC farm. Now I must remember to look for information about this as well. (Should I have posted this in the "You know you are addicted..." thread instead?) I'm quite serious. (But maybe I will do other things as well.)

[wpolly]

My Per-iteration time reduced to 49ms With Prime95 V23.4.......... :(

Hopes that George will do further improvements on the P4 code.

[lycorn]

wpolly wrote:

My Per-iteration time reduced to 49ms With Prime95 V23.4.

What model of PC and FFT size are you referring to?

[markhl]

If you are using onboard video, the video settings can make a big difference, like 25%!
Work-around: right-click an empty area of the desktop, choose Properties, Settings tab. Use minimal video settings like 640*480, 8-bit color. On the Advanced button, go to the monitor tab and choose the lowest refresh rate.
Fix: get a PCI or AGP video card.

See the thread http://www.mersenneforum.org/viewtopic.php?t=830 .
Edit: sometimes 8-bit color may not give you the best performance, if the CPU has to dither 16 bits down to 8 bits. It's best to check a few settings for your best performance.

[wpolly]

With 1024*768: 51.220ms
With 800*600: 54.765ms
Looks like that The performance INCREASES with the resolution!!!???

PS: My computer is P4 2.0G/512M/GF4 MX440, working on 1024K FFT Size.

[ET_]

With 1024*768: 51.220ms
With 800*600: 54.765ms
Looks like that The performance INCREASES with the resolution!!!???

AFAIK 800.600 resolution has a non-standard refresh time that has to be set and it might require some CPU time.

Luigi

[Blaise Pascal]

Originally Posted by QuintLeo

I'd go with the cache size as the primary difference - PIII had a 256k cache IIRC in the 550s, vs. a 128K cache in the Celerons - this has a *major* effect on Prime, which is memory-intensive.

IIRC, not all Celerons have 128KB cache. The Tualatin-based Celerons, which 1.1ghz is a possible speed, have 256KB cache.

EDIT: moved my iteration times to the benchmark thread

BP

0007

[Xyzzy]

The mobile P4-based Celerons have 256KB also...

[tom11784]

Originally Posted by QuintLeo

1280x1024 is a common resolution.

My computer's resolutions are:
640x480
800x600
848x480
1024x768
1152x864
1280x720
1280x768
1280x960
1280x1024
1360x768
1600x900
1600x1024
1600x1200


Also, here are some time trials for 10 iterations of 50,000,000 on my P4 2.4
Resolution - Colors - Time (s)
1152x864 - 32bit - 1.784
1152x864 - 16bit - 1.775
1152x864 - 256 - 1.782
1024x768 - 32bit - 1.798 - my regular setting
1024x768 - 16bit - 1.778
1024x768 - 256 - 1.803
800x600 - 32bit - 1.777
800x600 - 16bit - 1.777
800x600 - 256 - 1.788

So I'm running at 98.7% time efficiency, oh well