20% faster at same clock speeds !?!

irishgrizzly

macrumors 65816
Original poster
May 15, 2006
1,462
1
I've been reading the menron thread over in buying tips. I came across the line "I thought it was 20% faster at same clock speeds".

Now I've never paid much attention to clock speeds and Mhz numbers. But this confuses me. I've heard that it is not longer about clock speeds as people keep saying here. But how do you define the speed of a machine against another in numbers (without putting both through benchmark tests).

Can anyone explain this in layman's terms? I know two core are better then one, does this make a 2 core 1.8Mhz equal to a single core 3.6Mhz? :confused:
 

topgunn

macrumors 65816
Nov 5, 2004
1,462
1,342
Houston
irishgrizzly said:
I've been reading the menron thread over in buying tips. I came across the line "I thought it was 20% faster at same clock speeds".

Now I've never paid much attention to clock speeds and Mhz numbers. But this confuses me. I've heard that it is not longer about clock speeds as people keep saying here. But how do you define the speed of a machine against another in numbers (without putting both through benchmark tests).

Can anyone explain this in layman's terms? I know two core are better then one, does this make a 2 core 1.8Mhz equal to a single core 3.6Mhz? :confused:
It means that it can complete 20% more work units at the same clock speed. This is a theoretical figure released by Intel. Basically, the Merom is the same processor as the Core Duo but it has added instruction sets as well as 64-bit capabilities.

And no, a 1.8GHz dual core CPU does not equal a single core 3.6GHz. A program has to be able to support multiple processors. If it doesn't, it will just use one. Now, if the OS is smart enough, it can have two applications that don't support multiple processors and run them each on a different core. For more information, read the guide here.
 

BlizzardBomb

macrumors 68030
Jun 15, 2005
2,537
0
England
irishgrizzly said:
Now I've never paid much attention to clock speeds and Mhz numbers. But this confuses me. I've heard that it is not longer about clock speeds as people keep saying here. But how do you define the speed of a machine against another in numbers (without putting both through benchmark tests).
The easiest way is to look at how modern the chip is. Pentium 4 will be outperformed by a Core Duo (even at a lower clock speed) and the Core 2 Duo will outperform a Core Duo at the same clock speed.

irishgrizzly said:
I know two core are better then one, does this make a 2 core 1.8Mhz equal to a single core 3.6Mhz? :confused:
Sadly not, as there are inefficiencies. If it were true the Quad Power Mac would be running at 10GHz :eek: :D
 

dpaanlka

macrumors 601
Nov 16, 2004
4,868
6
Illinois
topgunn said:
A program has to be able to support multiple processors. If it doesn't, it will just use one. Now, if the OS is smart enough, it can have two applications that don't support multiple processors and run them each on a different core.
When the 9500 and 9600 multiprocessor Macs were released, how did Mac OS 7 handle this? Was it smart enough to juggle processors? I know there is a multiprocessing extension for the operating system. What does it do?
 

velocityg4

macrumors 601
Dec 19, 2004
4,719
1,286
Georgia
dpaanlka said:
When the 9500 and 9600 multiprocessor Macs were released, how did Mac OS 7 handle this? Was it smart enough to juggle processors? I know there is a multiprocessing extension for the operating system. What does it do?
Basically it used only one processor most of the time. Though some programs like photoshop were able to use all processors. I just don't understand why these machines were not supported in Mac OS X. Since a dual 300mhz 604e had to outperform a single 233mhz G3 iMac.
 

MacDonaldsd

macrumors 65816
Sep 8, 2005
1,005
0
London , UK
irishgrizzly said:
I've been reading the menron thread over in buying tips. I came across the line "I thought it was 20% faster at same clock speeds".

Now I've never paid much attention to clock speeds and Mhz numbers. But this confuses me. I've heard that it is not longer about clock speeds as people keep saying here. But how do you define the speed of a machine against another in numbers (without putting both through benchmark tests).

Can anyone explain this in layman's terms? I know two core are better then one, does this make a 2 core 1.8Mhz equal to a single core 3.6Mhz? :confused:
I think that a dual core 1.8 ghz has a 50% in real time increase other a single core, so a 2.7 GHz. (im sure i read that some where) like mentioned above the os and applications have to take advantage of this and it still carried out over the same bus.