PDA

View Full Version : Just how important is lot's of cache for video and rendering work?



sbrandt
08-03-2004, 02:20 AM
At ZipZoomFly I found some great prices on 90nm 533 Celerons w/256KB cache, and it started me to thinking ....(quick someone get me an aspirin).... just how important IS lot's of chip cache for VIDEO work anyway?
Are the SSE2 and high MHz more important, or is the 512KB or 1MB or larger cache essential?

Fer' instance... would a good board with a phat Celeron make a good LW, Vegas or Premiere box?

Ted, Eugene, Jim, D.J., can some of you REAL brainoids fill me in?

digimassa
08-03-2004, 09:17 AM
:cool:

AFAIK celerons suck on floating -point operations so they are less useable for rendering work

Lightwolf
08-03-2004, 09:45 AM
Originally posted by digimassa
AFAIK celerons suck on floating -point operations so they are less useable for rendering work
The only difference between Celerons and P4s is the amount of cache and the front side bus.
And _both_ suck on fp work, unless the app makes heavy use of SSE2 to counter the shortcomings of the fpu...

As far as 3D rendering is concerned, it is the speed of the cache that is more important than the size of it. Most rendering code fits in a cache, and memory access doesn't happen that often (texture access etc.) compared to the rendering loops.

This might be different for video apps, where you'd want a high memory/CPU bandwidth as well as SSE2 and stuff like that. I'm not sure what role the cache plays here though.
P4s (the EE series) with a larger cache at the same clockspeed gain realitvely little performance (5%-10%) and cost a lot more. And the new Prescotts are in some cases even slower then their predecessor.

Cheers,
Mike

veljko
08-04-2004, 02:20 PM
what would your choice for a proccessor be lightwolf?

Lightwolf
08-05-2004, 02:52 AM
Originally posted by veljko
what would your choice for a proccessor be lightwolf?
Well, if I had the cash Opteron250s :)
Since I don't, Xeons (not the new Prescotts though).

I work on a Xeon 3.06 Dual machine here (Asus PC-DL board, no good for video, since it only has 32bit PCI) for compositing and 3D.
Our renderfarm consists of 5 dual Athlon MP 2800s, since they provide the most bang for the buck.

Cheers,
Mike

digimassa
08-05-2004, 03:27 AM
:cool:
Athlons suck in rendering

Lightwolf
08-05-2004, 03:32 AM
Originally posted by digimassa
:cool:
Athlons suck in rendering
Well, not according to the results I got here. If I render volumetrics, the MPs easily beat my Xeon.
In other instances (straight render, a bit of radiosity), they are roughly 80% or so of the speed of the Xeon, but only cost me around 1000,- Eur a pop (1GB Ram each, I did re-use old HDs etc...).
Which is not bad, considering that my workstation did cost twice as much.

Cheers,
Mike

digimassa
08-05-2004, 04:13 AM
Originally posted by Lightwolf
...If I render volumetrics, the MPs easily beat my Xeon....


Strange, my experience is that the more volumetrics the more difference in renderspeed between Pentium and Athlon^^

Lightwolf
08-05-2004, 04:20 AM
Originally posted by digimassa
Strange, my experience is that the more volumetrics the more difference in renderspeed between Pentium and Athlon^^
Yep, mine too, the Athlons get a lot faster ;) (OgoTaiki in my case).
Is that a P4 or a PIII you're reffering to?

Cheers,
Mike

Matt
08-05-2004, 05:03 AM
:eek: Please tell me my new system will be nice and fast!

Asus P4C800-E Deluxe Motherboard
Intel Pentium 4 3400 Retail 512k (478) 800 HT
1024mb Dual Channel PC3200 Premium Kit OCZ
Gainward Ultra 2600 GeForce6800 Ultra Graphics Card

Pleeeeeease!!! :)

Lightwolf
08-05-2004, 05:12 AM
Well, it is good for a single Processor system...

Nowadays I'd go for an Athlon FX though ;)

Cheers,
Mike

Matt
08-05-2004, 05:44 AM
Couldn't afford to go dual, so I went for the fastest single I could afford!

Edit: I'll probably go 64 bit when most of the apps I use take advantage of it (be time to upgrade then anyway!) Otherwise it's money for nothing at the moment!