CPU speeds and bus speeds.

As I understand it, whilst CPU speeds have increased several fold over
the past 10 years, bus speeds have barely doubled.

So.. is your Pentium 9. 'SuperFat*******' 4.0 GHZ CPU really going to things
15 times faster than my Cyrix 'Tortoise' 266 Mhz?

half_pint.

On Sun, 18 Apr 2004 03:09:50 +0100, "half_pint"
wrote:

As I understand it, whilst CPU speeds have increased several fold over
the past 10 years, bus speeds have barely doubled.

So.. is your Pentium 9. 'SuperFat*******' 4.0 GHZ CPU really going to things
15 times faster than my Cyrix 'Tortoise' 266 Mhz?

half_pint.


Considering that Cyrix was a PR rated chip (actual speed was probably
200mhz), with marginal performance partly caused by a small cache and very
poor FPU, I would expect that many current processors would be 15 times as
fast. Add in much faster memory, faster disk drives, much faster video
cards, basically faster everything, and a 15x speed up is not really that
far fetched. That is unless you are still stuck on a 56k dial up
internet connection, in which case your internet is just about as slow as
it ever was.

JT

"half_pint" wrote in message
...
As I understand it, whilst CPU speeds have increased several fold over
the past 10 years, bus speeds have barely doubled.

So.. is your Pentium 9. 'SuperFat*******' 4.0 GHZ CPU really going to
things
15 times faster than my Cyrix 'Tortoise' 266 Mhz?

half_pint.


Your Cyrix's 66Mhz system bus is quite a bit slower than a newer P4's 200Mhz
Quad-Pumped (effectively 800Mhz) system bus. That's over a 12x increase in
raw bus bandwidth right there. Additonally, the 66Mhz SDRAM your system is
probably running can only transfer 500MB/sec or so (I don't even remember
any chipsets actually ever managed to hit that kind of theoretical speed
anyways). Compared to a modern dual-channel DDR400 system that can push
5-6GB of memory bandwidth, that's about 10x slower. So yeah, there's a huge
difference in speed....

-Eric

half_pint wrote:

As I understand it, whilst CPU speeds have increased several fold over
the past 10 years, bus speeds have barely doubled.

So.. is your Pentium 9. 'SuperFat*******' 4.0 GHZ CPU really going to things
15 times faster than my Cyrix 'Tortoise' 266 Mhz?

half_pint.



Is this a trick question?

Just for the sake of the uninformed, while the latest processors,
especially ones from a certain brand (*cough*Intel*cough*), are a bit
ridiculous with their 733 mHz busses and multiple gigahertz CPU's, they
are going to be just a tad bit faster than your old Cyrix. A tad being
relative, when I say a tad faster, I mean something like Niagara Falls
puts out a tad of water.

"JT" wrote in message
s.com...
On Sun, 18 Apr 2004 03:09:50 +0100, "half_pint"

wrote:

As I understand it, whilst CPU speeds have increased several fold over
the past 10 years, bus speeds have barely doubled.

So.. is your Pentium 9. 'SuperFat*******' 4.0 GHZ CPU really going to
things
15 times faster than my Cyrix 'Tortoise' 266 Mhz?

half_pint.


Considering that Cyrix was a PR rated chip (actual speed was probably
200mhz), with marginal performance partly caused by a small cache and very
poor FPU, I would expect that many current processors would be 15 times
as
fast. Add in much faster memory, faster disk drives, much faster video
cards, basically faster everything, and a 15x speed up is not really
that
far fetched. That is unless you are still stuck on a 56k dial up
internet connection, in which case your internet is just about as slow as
it ever was.

I think the limit on bus speed is about 200mhz without 'tricks'.
My machine is capable of surfing the net just as fast as one
with a 'SuperFat*******' processor. CPU speed is irrelevant
surfing speed to, just as the size of the ash tray is irrelevant to
a cars top speed.

JT

"Eric Gross" wrote in message
...
"half_pint" wrote in message
...
As I understand it, whilst CPU speeds have increased several fold over
the past 10 years, bus speeds have barely doubled.

So.. is your Pentium 9. 'SuperFat*******' 4.0 GHZ CPU really going to
things
15 times faster than my Cyrix 'Tortoise' 266 Mhz?

half_pint.


Your Cyrix's 66Mhz system bus is quite a bit slower than a newer P4's
200Mhz
Quad-Pumped (effectively 800Mhz) system bus. That's over a 12x increase in
raw bus bandwidth right there. Additonally, the 66Mhz SDRAM your system is
probably running can only transfer 500MB/sec or so (I don't even remember
any chipsets actually ever managed to hit that kind of theoretical speed
anyways). Compared to a modern dual-channel DDR400 system that can push
5-6GB of memory bandwidth, that's about 10x slower. So yeah, there's a
huge
difference in speed....

-Eric

I was looking at a chart posted in this group (recently) which showed the
history
of cpu and bus speeds. I was surprised at how low the modern bus speeds
were on may of the newer models whilst the cpu speed seemed to
have increased considerably.
A lot of the bus speeds were 100mhz which is not much faster than my 66mhz.
Some were a bit higher but they looked very recent ones with various
'tricks'

Unfortunately I cant find the chart again so I would be thanful if someone
could repost the link.


But will not harddrive speeds be basically the same anyway? 5400, 7200?
Making bus speed irrelvant on many operations?

"half_pint" wrote in message
...
I think the limit on bus speed is about 200mhz without 'tricks'.
My machine is capable of surfing the net just as fast as one
with a 'SuperFat*******' processor. CPU speed is irrelevant
surfing speed to, just as the size of the ash tray is irrelevant to
a cars top speed.

I don't see why you call the ways that bus speeds have increased "tricks."
Sure, the clock may be at only 200Mhz, but if you're transferring 4 pieces
of data every clock cycle, it is identical to an 800Mhz bus transferring one
piece of data per cycle. It removes the problem of distributing an 800Mhz
clock across a bus yet gets the same bandwidth.

As for CPU speed not affecting your websurfing speed, you're right that it
doesn't quite matter the difference between say a 3Ghz processor and a 4Ghz
one. However, modern pages using very complex nested tables and style sheets
are going to render a heck of a lot slower on your 200Mhz Cyrix than a
faster CPU. Perhaps you're using an outdated browser which doesn't handle
any of the fancy new additions and so you don't notice the speed difference?
Try downloading Mozilla 1.4 and tell me how many minutes (hours?) it takes
to start up on your Cyrix...

-Eric

"half_pint" wrote in message
...

"Eric Gross" wrote in message
...
"half_pint" wrote in message
...
As I understand it, whilst CPU speeds have increased several fold over
the past 10 years, bus speeds have barely doubled.

So.. is your Pentium 9. 'SuperFat*******' 4.0 GHZ CPU really going to
things
15 times faster than my Cyrix 'Tortoise' 266 Mhz?

half_pint.


Your Cyrix's 66Mhz system bus is quite a bit slower than a newer P4's
200Mhz
Quad-Pumped (effectively 800Mhz) system bus. That's over a 12x increase
in
raw bus bandwidth right there. Additonally, the 66Mhz SDRAM your system
is
probably running can only transfer 500MB/sec or so (I don't even
remember
any chipsets actually ever managed to hit that kind of theoretical speed
anyways). Compared to a modern dual-channel DDR400 system that can push
5-6GB of memory bandwidth, that's about 10x slower. So yeah, there's a
huge
difference in speed....

-Eric

I was looking at a chart posted in this group (recently) which showed the
history
of cpu and bus speeds. I was surprised at how low the modern bus speeds
were on may of the newer models whilst the cpu speed seemed to
have increased considerably.
A lot of the bus speeds were 100mhz which is not much faster than my
66mhz.
Some were a bit higher but they looked very recent ones with various
'tricks'

Unfortunately I cant find the chart again so I would be thanful if someone
could repost the link.


Actually I have found it again.
http://www.tom.womack.net/x86FAQ/faq_time.html
Thats one for my favourites folder.

Take this line as an example. I know there are faster ones though.

15/05/02 Intel Celeron 1400 100 FCPGA2 Tualatin/256k

It has a bus speed of 100mhz not that much faster than mine,
and I think I could have bought a PC with a 100mhz bus when
I bought mine (if I was made of money).
Anyway its bus speed is 50% faster than mine but its CPU
speed is around 300% faster.


But will not harddrive speeds be basically the same anyway? 5400, 7200?
Making bus speed irrelvant on many operations?

"half_pint" wrote in message
...
15/05/02 Intel Celeron 1400 100 FCPGA2 Tualatin/256k

It has a bus speed of 100mhz not that much faster than mine,
and I think I could have bought a PC with a 100mhz bus when
I bought mine (if I was made of money).
Anyway its bus speed is 50% faster than mine but its CPU
speed is around 300% faster.

Yes, but keep in mind CPU's are designed to rely on *not* having to go to
the main bus for every piece of data. That is why we have caching. The
Tualatin you mentioned has 256KB of *on-die* cache running at full speed of
the processor. This is a heck of a lot faster than the external cache
sitting on the slow system bus that your Cyrix uses. By having a built-in
cache running at the full speed of the processor, the processors scale in
overall speed much better than being tied to a cache running at a slow,
fixed speed on the motherboard.

While memory bandwidth is important in many applications, raw cpu power is
often all that's needed. If you have an optimized algorithm that fits
entirely into the large cache on newer CPU's, the bus speed becomes
practically irrelevant to performance. Everyday applications do still get
benefit from faster bus speeds, but raw CPU power can make a huge difference
in many cases.

-Eric

On Sun, 18 Apr 2004 22:41:51 +0100, "half_pint"
wrote:


"JT" wrote in message
ws.com...
On Sun, 18 Apr 2004 03:09:50 +0100, "half_pint"

wrote:

As I understand it, whilst CPU speeds have increased several fold over
the past 10 years, bus speeds have barely doubled.

So.. is your Pentium 9. 'SuperFat*******' 4.0 GHZ CPU really going to
things
15 times faster than my Cyrix 'Tortoise' 266 Mhz?

half_pint.


Considering that Cyrix was a PR rated chip (actual speed was probably
200mhz), with marginal performance partly caused by a small cache and very
poor FPU, I would expect that many current processors would be 15 times
as
fast. Add in much faster memory, faster disk drives, much faster video
cards, basically faster everything, and a 15x speed up is not really
that
far fetched. That is unless you are still stuck on a 56k dial up
internet connection, in which case your internet is just about as slow as
it ever was.

I think the limit on bus speed is about 200mhz without 'tricks'.
Lets just do a couple quick calculations here. According to what I can
find, your Cyrix is actually runnign at 3.5*66 (real speed 233). Means your
memory is running at 66mhz. raw clock speed, DDR 400 is 6 times as fast.
Make that Dual Channel, and you are 12 times as fast. Just on data that is
transferred to and from memory. DDR is not a "trick", but a better
technology. Same with dual channel.

My machine is capable of surfing the net just as fast as one
with a 'SuperFat*******' processor. CPU speed is irrelevant
surfing speed to, just as the size of the ash tray is irrelevant to
a cars top speed.

As long as there is no multimedia, streaming video, video conferencing,
etc.. that make use of high compression ratios and lots of processor to
make up for the low band width you can get by. Throw in even a simple
online game on any broadband connection, and your Cyrix isn't even in the
game. As long as you just use it for Usenet, basic email, and other simple
browsing, you can get by for a little while longer. We are talking drive
trains and engines, not ashtrays to stay with you attempted automotive
analogy.

JT

JT