What really determines CPU Speed

[Avitar]

Okay, so I'll try to make this quick. I was reading my textbook today and I came across this:

Now the funny thing is, after viewing many sites that give "detailed" specs on processors, none of them really said what the BUS width on the processor was. That's odd. Now I tried some advanced system utilities like Cupid CPU Z and others trying to locate the said BUS width. Funny, none of them detected it.. Now if BUS width is one of the key factors in determining system performance, why the heck can't I find it out? :o

Can someone please tell me what or how to find out the BUS width on the AMD A6-4400M APU?

Update: Using Cupid HW Monitor Pro I was able to get the following SMBus Data. I do not know how to interpret it nor calculate the width from the data given. I just wanna know what the width is!! Why do manufacturers NOT list this spec on the CPU's??

CPUID SMBus Report

-------------------------------------------------------------------------

Binaries

-------------------------------------------------------------------------

HWMonitorPro version 1.1.7.0

SMB device I/O = 0xB00, address 0x50, channel = 0

SMBus registers

00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F

00 92 10 0B 03 03 19 00 09 03 52 01 08 0C 00 3E 00

10 69 78 69 30 69 11 20 89 00 05 3C 3C 00 F0 83 81

20 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

30 00 00 00 00 00 00 00 00 00 00 00 00 0F 11 45 00

40 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

50 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

60 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

70 00 00 00 00 00 01 98 07 11 43 84 3C 3C B9 C7 92

80 39 39 55 35 34 32 38 2D 30 34 30 2E 41 30 31 4C

90 46 20 00 00 00 00 00 00 00 00 00 00 00 00 00 00

A0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

B0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

C0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

D0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

E0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

F0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 5A

SMB device I/O = 0xB00, address 0x51, channel = 0

SMBus registers

00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F

00 92 11 0B 03 03 19 00 09 03 52 01 08 0A 00 FE 00

10 69 78 69 30 69 11 18 81 00 05 3C 3C 00 F0 83 05

20 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

30 00 00 00 00 00 00 00 00 00 00 00 00 0F 11 05 00

40 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

50 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

60 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

70 00 00 00 00 00 80 AD 01 12 34 05 62 A2 14 22 C0

80 48 4D 54 33 35 31 53 36 43 46 52 38 43 2D 50 42

90 20 20 4E 30 80 AD 00 57 56 32 38 4E 30 35 35 33

A0 32 30 38 00 01 03 02 04 03 03 03 02 00 00 00 00

B0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

C0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

D0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

E0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

F0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

Edited November 9, 2013 by Avitar

[Kalju]

Probably fairy tales existed already in your childhood. Do they still believe that? Or were they necessary for something else?

All, that is written, isn't always quite the right. But that does not mean that it would also be quite wrong.

In every fairy tale is a bit of wisdom inside.

[Avitar]

Probably fairy tales existed already in your childhood. Do they still believe that? Or were they necessary for something else?

All, that is written, isn't always quite the right. But that does not mean that it would also be quite wrong.

In every fairy tale is a bit of wisdom inside.

What does that have to do with BUS width and CPU performance? :huh:

[Nima]

Hello there :hi:,

CPU frequency is determined by two factors, one is multiplier and the other one is FSB or Front Side Bus; so, for changing the CPU frequency you need to either change multiplier or FSB.

CPU Multiplier can be changed easily and it's possible in almost all CPUs (specially in Unlocked or Black CPUs) but changing FSB is not that easy, it's should be changed via the System Management Bus.

There are only two disadvantages:

1. You must know the vendor and the version number of the PLL IC that is responsible for the FSB frequency.

There are two possibilities to find the version of PLL IC. The first is that it is already implemented in CPUCooL, second you must look at your motherboard. There are several IC's and a crystal with a value of 14.3 MHz typed on top, it is next to this crystal that the IC's normally reside. Then you should look at the supported PLL's and if there is a match you are the winner.

Here are some examples:

http://www.cpufsb.de/577.JPG

http://www.cpufsb.de/8864.jpg

http://www.cpufsb.de/914817.JPG

http://www.cpufsb.de/924839.JPG

2. Speeding the Front Side Bus can be critical thing because you leave the specifications of the chip producer, it is possible to blow your CPU.

For changing FSB there are some other ways, for example you can do that with small utility named CPUFSB.

About FSB and Bus Speed in BIOS menu, it's a little bit complicated.

For example, in Athlon 1.33 GHz 266FSB Socket A CPU, The multiplier should be 10x and the speed should be 1333 but most motherboards cannot detect which bus speed it is, for 133 bus they need to be set manually 133 is 266 DDR, so you don't actually see a 266 setting in BIOS.

If you really want to see your CPU FSB, most probably your motherboard should show that value in BIOS setting, if not, you can check that in CPU-Z.

For example, I own AMD Phenom II X4 945 CPU, my CPU Multiplier set at x15.0 and my FSB is 200MHz so it gives me 3.0GHz Frequency. :)

About your CPU, as I see, your CPU runs default on 2.7Ghz with multiplier of x27.0, so your FSB is 100MHz. :)

You can divide frequency by multiplier to find your FSB. ;)

Hope you get it. ^_^

Edited November 9, 2013 by Nima

[Avitar]

Hello there :hi:,

CPU frequency is determined by two factors, one is multiplier and the other one is FSB or Front Side Bus; so, for changing the CPU frequency you need to either change multiplier or FSB.

CPU Multiplier can be changed easily and it's possible in almost all CPUs (specially in Unlocked or Black CPUs) but changing FSB is not that easy, it's should be changed via the System Management Bus.

There are only two disadvantages:

1. You must know the vendor and the version number of the PLL IC that is responsible for the FSB frequency.

There are two possibilities to find the version of PLL IC. The first is that it is already implemented in CPUCooL. Please email me your board type and PLL IC and it will be added to the list. If it is not in the list, you must look at your motherboard. There are several IC's and a crystal with a value of 14.3 MHz typed on top, it is next to this crystal that the IC's normally reside. Then you should look at the supported PLL's and if there is a match you are the winner.

Here are some examples:

http://www.cpufsb.de/577.JPG

http://www.cpufsb.de/8864.jpg

http://www.cpufsb.de/914817.JPG

http://www.cpufsb.de/924839.JPG

2. Speeding the Front Side Bus can be critical thing because you leave the specifications of the chip producer, it is possible to blow your CPU.

For changing FSB there are some other ways, for example you can do that with small utility named CPUFSB.

About FSB and Bus Speed in BIOS menu, it's a little bit complicated.

For example, in Athlon 1.33 GHz 266FSB Socket A CPU, The multiplier should be 10x and the speed should be 1333 but most motherboards cannot detect which bus speed it is, for 133 bus they need to be set manually 133 is 266 DDR, so you don't actually see a 266 setting in BIOS.

If you really want to see your CPU FSB, most probably your motherboard should show that value in BIOS setting, if not, you can check that in CPU-Z.

For example, I own AMD Phenom II X4 945 CPU, my CPU Multiplier set at x15.0 and my FSB is 200MHz so it gives me 3.0GHz Frequency. :)

About your CPU, as I see, your CPU runs default on 2.7Ghz with multiplier of x27.0, so your FSB is 100MHz. :)

You can divide frequency by multiplier to find your FSB. ;)

Hope you get it. ^_^

FINALLY AN EDUCATED ANSWER! :D

Hello friend :wave:

I understand all of the information you just presented. But how can we determine the "number of lines" in the BUS?

All I can see is that the Bus Speed is 100.88Mhz. Not the number of lines or the width or bandwidth.

EDIT: This a laptop by the way. I don't want to change anything. I just want to find out what the width is for the System BUS. Not the speed, not the frequency, just he width. So I can do some small calculations with the registers.

Edited November 9, 2013 by Avitar

[ajdibi]

http://www.cpu-world.com/CPUs/Bulldozer/AMD-A6-Series%20A6-4400M.html - look under "Data width".

[Nima]

I don't think they they publish at that much detail, I also could not find at their website; for that much detail, you would need to contact AMD and see if you can get your hands on a full data sheet. The ones they have online are generic and don't truly tell you anything other than 64-bit and how many PCIe lanes or memory bandwidth they can handle without additional controllers. :unsure:

Although, Intel publishes detailed information for some of their series (like Xeon). ;)

[Avitar]

http://www.cpu-world.com/CPUs/Bulldozer/AMD-A6-Series%20A6-4400M.html - look under "Data width".

Yes friend, I've been to that page. However "Data Width" is not the same as "Bus Width." Data width refers to the RAM Addressable and processor register handlers. BUS width is the number of connectors between the CPU and the L1 Cache. It's the latter I want to find out.

[Avitar]

I don't think they they publish at that much detail, I also could not find at their website; for that much detail, you would need to contact AMD and see if you can get your hands on a full data sheet. The ones they have online are generic and don't truly tell you anything other than 64-bit and how many PCIe lanes or memory bandwidth they can handle without additional controllers. :unsure:

Although, Intel publishes detailed information for some of their series (like Xeon). ;)

I really frown on this practise by AMD. A simple thing as this you can't figure out..

[Nima]

I don't think they they publish at that much detail, I also could not find at their website; for that much detail, you would need to contact AMD and see if you can get your hands on a full data sheet. The ones they have online are generic and don't truly tell you anything other than 64-bit and how many PCIe lanes or memory bandwidth they can handle without additional controllers. :unsure:

Although, Intel publishes detailed information for some of their series (like Xeon). ;)

I really frown on this practise by AMD. A simple thing as this you can't figure out..

The reason is easy, there is no need for anyone to go that much detail in their products, especially in their new series, A and FX which these models are their 'top' and 'flagship' and AMD has nothing but them, they can not compete with Intel in any aspect, so they don't want to lose even the things they have right now, it's the politics of every company, which try to keep secret some of their technologies or information which is technical, it's enough for normal users to know their CPU support 64-bit and no more. :D

I don't know where, but some people spent some time on Intel CPUs and managed to find some very technical information, such as Bus width you said, for example, as I remember, Core i7 990X was 192-bit while AMD Phenom II X6 1100T was 128-bit. ;)

[nIGHT]

I don't know where, but some people spent some time on Intel CPUs and managed to find some very technical information, such as Bus width you said, for example, as I remember, Core i7 990X was 192-bit while AMD Phenom II X6 1100T was 128-bit. ;)

I just notice this.

Core i7 990X is a 6 core cpu while AMD Phenom II X6 1100T is a Quad-core cpu.

for 32-bit computing:

Core i7 990X

32 bit * 6 = 192 bit

AMD Phenom II X6 1100T

32 bit * 4 = 128 bit

Core i7 990X is a 6 core cpu while AMD Phenom II X6 1100T is a Quad-core cpu.

for 64-bit computing:

Core i7 990X

64 bit * 6 = 384 bit

AMD Phenom II X6 1100T

64 bit * 4 = 256 bit

Edited November 9, 2013 by nIGHT

[Nima]

I don't know where, but some people spent some time on Intel CPUs and managed to find some very technical information, such as Bus width you said, for example, as I remember, Core i7 990X was 192-bit while AMD Phenom II X6 1100T was 128-bit. ;)

I just notice this.

Core i7 990X is a 6 core cpu while AMD Phenom II X6 1100T is a Quad-core cpu.

for 32-bit computing:

Core i7 990X

32 bit * 6 = 192 bit

AMD Phenom II X6 1100T

32 bit * 4 = 128 bit

Core i7 990X is a 6 core cpu while AMD Phenom II X6 1100T is a Quad-core cpu.

for 64-bit computing:

Core i7 990X

64 bit * 6 = 384 bit

AMD Phenom II X6 1100T

64 bit * 4 = 256 bit

No, you are wrong, AMD Phenom II X6 series are all a native hexa-core (6 Cores) die design with no disabled cores. :think:

[locoJoe]

The fastest computer I ever seen was tossed out a 8th floor window. I dunno if it had time to reach terminal velocity but it was movin' fast. Until it hit the pavement!

[Avitar]

I'm honestly fed up of this. I opened the damn thing and counted the wires leading out of the CPU. There were 64 on each side = 128bits.

[nIGHT]

I'm honestly fed up of this. I opened the damn thing and counted the wires leading out of the CPU. There were 64 on each side = 128bits.

I think they are not for both input and output rather the one side (first 64 bit/wires) is for input going to the cpu and the other side (2nd 64 bit/wires) is for output from the cpu. :think: So for me as I understand based on your post, the bus is 64 bit (bit/wires), or 64 wires for input and another 64 wires for output.

So my post above and assumption that is based on what nima has said about 192bit is wrong.

I think we should take the highest state the cpu can operate (32bit/64bit), this we should take the 64 bit which also means 64 pieces of wires too going in and another 64 pieces of wires going out? :think:

I don't know where, but some people spent some time on Intel CPUs and managed to find some very technical information, such as Bus width you said, for example, as I remember, Core i7 990X was 192-bit while AMD Phenom II X6 1100T was 128-bit. ;)

I just notice this.

Core i7 990X is a 6 core cpu while AMD Phenom II X6 1100T is a Quad-core cpu.

for 32-bit computing:

Core i7 990X

32 bit * 6 = 192 bit

AMD Phenom II X6 1100T

32 bit * 4 = 128 bit

Core i7 990X is a 6 core cpu while AMD Phenom II X6 1100T is a Quad-core cpu.

for 64-bit computing:

Core i7 990X

64 bit * 6 = 384 bit

AMD Phenom II X6 1100T

64 bit * 4 = 256 bit

Edited November 9, 2013 by nIGHT