Hi Dan3; Well, I finally went and looked at the
SharkyExtreme benchmarks, and here is what I saw.
First of all, I should note that I am not a high-level
guy like you. I design things from the gates up to the
chip level. I don't spec systems or anything like that.
A man's got to know his limitations, and one of my
limitations is that I don't know much about high modern
PC architecture.
That means I have to simplify things before I can
understand them. The question is how much does RDRAM
help? Unfortunately, since RDRAM and SDRAM take different
chip sets, this isn't easy to figure out. But we can look
at the combination of RDRAM+i820@133MHz and
SDRAM+440BX@100MHz, each with a 600MHz Katmai processor:
In addition to comparing RDRAM to SDRAM, I am also
comparing the coppermine to the previous silicon.
First column is 100MHz SDRAM, Katmai, 440BX.
Second coumn is 133MHz RDRAM, Katmai, i820.
Third column is 100MHz SDRAM, Coppermin, 440BX.
Katmai Copper
------------ mine
440BX i820 440BX
/100 B/133 E/100
Speed Improvements
-------------------- ------------
BM SDRAM RDRAM Copper RDRAM Copper
---- ----- ----- ------ ----- ------
10.1 67.4 71.9 69.1 6.7% 2.5%
10.2 9570 9450 9440 -1.3 -1.4
11.1 60.1 64.8 63.2 7.8 5.2
11.2 84.0 88.9 94.2 5.8 12.1
12.1 43.9 44.4 56.0 1.1 26.1
12.2 3055 3050 3240 -0.2 6.1
13.1 224 244 268 8.9 19.6
13.2 78.9 79.4 86.2 0.6 9.3
Delay
--------------------
BM SDRAM RDRAM Copper
---- ----- ----- ------
14.1 110.9 97.5 93.3 13.7 18.9
14.2 318.6 279.1 279.1 14.1 14.1
RDRAM Copper
----- ------
Average Improvements: 5.7% 11.2%
You noted that some of the 5.7% RDRAM improvement will
disappear when the bus on the BX design is changed from 100
to 133 MHz, and the SDRAM is switched to PC133 (with CAS
delay of 2, presumably). I believe that this is true, but
some of the benchmarks listed above are CPU only, and will
not change much.
As an AMD investor, my favorite quote was: "In our own
testing we achieved a top speed of 840MHz with our Pentium
III 733 Coppermine CPU, although stability was barely
practical for the average user to endure and it was only
possible to hit on a specially unlocked engineering sample
CPU provided by a friendly OEM system builder."
The Athlon still looks like a winner to me.
-- Carl |
