# CPU speed vs RAM speed

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Greetings.
I have a 3 general questions.  If I understand my readings so far, the FSB
(Front Side Bus) is the speed at which the CPU delivers / accepts data
outside of itself. The processing speed of the CPU is rated by the FSB
multiplied by a number set by the manufacturer, which seems to be adjustable
Question 1 (two part): Since RAM chips are rated with a set speed, how can
one expect all data processed through them to be as fast as the CPU?  Won't
the RAM slow things down becoming a bottleneck?  My benchmark readings is
showing that I have a CPU of 6 x 133Mhz (~800Mhz), and my RAM is PC100 not
the PC133.
Question 2: I have 3 slots for memory with 2 used for 128MB and 1 for 256MB.
Does it make a difference in which order they are placed in the slots (banks
0,1,2)?
Question 3: If one RAM is rated at 133Mhz and the other two rated at 100Mhz,
will that be a problem?

Thank you for your time in helping me understand what I'm doing.
Best regards,
Kevin

## Re: CPU speed vs RAM speed

'General Mailbox' wrote:
| I have a 3 general questions.  If I understand my readings so far, the FSB
| (Front Side Bus) is the speed at which the CPU delivers / accepts data
| outside of itself. The processing speed of the CPU is rated by the FSB
| multiplied by a number set by the manufacturer, which seems to be
| from reading in this newsgroup.
| Question 1 (two part): Since RAM chips are rated with a set speed, how can
| one expect all data processed through them to be as fast as the CPU?
Won't
| the RAM slow things down becoming a bottleneck?  My benchmark readings is
| showing that I have a CPU of 6 x 133Mhz (~800Mhz), and my RAM is PC100 not
| the PC133.
| Question 2: I have 3 slots for memory with 2 used for 128MB and 1 for
256MB.
| Does it make a difference in which order they are placed in the slots
(banks
| 0,1,2)?
| Question 3: If one RAM is rated at 133Mhz and the other two rated at
100Mhz,
| will that be a problem?
_____

The CPU multiplier for Core 2 Duo CPUs is adjustable; but except for the two
Extreme Core 2 CPUs the multiplier can only be set to stock or LOWER.  Your
CPU is much earlier, and has a fixed CPU multiplier that CAN NOT BE CHANGED.

#1.  Memory IS slower than the processing speed of CPUs.  Memory IS a
bottleneck.  However, there is a mitigating design factor;  the L1 cache
that is part of CPUs runs at the same speed as the CPU (with a bit of delay
in responding to a request) and the L2 cache that is part of Intel CPUs
since the early Pentium III CPUs also runs at the same speed as the CPU (but
with more delay than the L1 cache.)  As long as data and instructions are
already loaded in the L1 and L2 caches, that information is availiable
nearly as fast as the CPU can use it.

#2.  The order in which you place the memory probably makes no difference.
Try different combinations and check the results.  The motherboard manual

#3.  It is generally not a problem if different speed RAM modules are used
as long as the memory clock is set for the slower speed.  Your motherboard
may have a setting to allow setting the memory speed at PC100 while the FSB
is set at 133 MHz.  If your motherboard does not have such a setting, then
the PC100 memory may work at a FSB of 133 MHz.

Phil Weldon

| Greetings.
| I have a 3 general questions.  If I understand my readings so far, the FSB
| (Front Side Bus) is the speed at which the CPU delivers / accepts data
| outside of itself. The processing speed of the CPU is rated by the FSB
| multiplied by a number set by the manufacturer, which seems to be
| from reading in this newsgroup.
| Question 1 (two part): Since RAM chips are rated with a set speed, how can
| one expect all data processed through them to be as fast as the CPU?
Won't
| the RAM slow things down becoming a bottleneck?  My benchmark readings is
| showing that I have a CPU of 6 x 133Mhz (~800Mhz), and my RAM is PC100 not
| the PC133.
| Question 2: I have 3 slots for memory with 2 used for 128MB and 1 for
256MB.
| Does it make a difference in which order they are placed in the slots
(banks
| 0,1,2)?
| Question 3: If one RAM is rated at 133Mhz and the other two rated at
100Mhz,
| will that be a problem?
|
| Thank you for your time in helping me understand what I'm doing.
| Best regards,
| Kevin
|
|

## Re: CPU speed vs RAM speed

Thank you so much for your response, Phil.
It is informative and easy on the eyes.
Have a great day!
Kevin

|
| The CPU multiplier for Core 2 Duo CPUs is adjustable; but except for the
two
| Extreme Core 2 CPUs the multiplier can only be set to stock or LOWER.
Your
| CPU is much earlier, and has a fixed CPU multiplier that CAN NOT BE
CHANGED.
|
| #1.  Memory IS slower than the processing speed of CPUs.  Memory IS a
| bottleneck.  However, there is a mitigating design factor;  the L1 cache
| that is part of CPUs runs at the same speed as the CPU (with a bit of
delay
| in responding to a request) and the L2 cache that is part of Intel CPUs
| since the early Pentium III CPUs also runs at the same speed as the CPU
(but
| with more delay than the L1 cache.)  As long as data and instructions are
| already loaded in the L1 and L2 caches, that information is availiable
| nearly as fast as the CPU can use it.
|
| #2.  The order in which you place the memory probably makes no difference.
| Try different combinations and check the results.  The motherboard manual
|
| #3.  It is generally not a problem if different speed RAM modules are used
| as long as the memory clock is set for the slower speed.  Your motherboard
| may have a setting to allow setting the memory speed at PC100 while the
FSB
| is set at 133 MHz.  If your motherboard does not have such a setting, then
| the PC100 memory may work at a FSB of 133 MHz.
|
| Phil Weldon
|
| | Greetings.
| | I have a 3 general questions.  If I understand my readings so far, the
FSB
| | (Front Side Bus) is the speed at which the CPU delivers / accepts data
| | outside of itself. The processing speed of the CPU is rated by the FSB
| | multiplied by a number set by the manufacturer, which seems to be
| | from reading in this newsgroup.
| | Question 1 (two part): Since RAM chips are rated with a set speed, how
can
| | one expect all data processed through them to be as fast as the CPU?
| Won't
| | the RAM slow things down becoming a bottleneck?  My benchmark readings
is
| | showing that I have a CPU of 6 x 133Mhz (~800Mhz), and my RAM is PC100
not
| | the PC133.
| | Question 2: I have 3 slots for memory with 2 used for 128MB and 1 for
| 256MB.
| | Does it make a difference in which order they are placed in the slots
| (banks
| | 0,1,2)?
| | Question 3: If one RAM is rated at 133Mhz and the other two rated at
| 100Mhz,
| | will that be a problem?
| |
| | Thank you for your time in helping me understand what I'm doing.
| | Best regards,
| | Kevin
| |
| |
|
|