[2 days left] What’s wrong with your cloud strategy? Learn why multicloud solutions matter with Nimble Storage.Register Now

x
?
Solved

PC66 SDRAM VS PC100 SDRAM

Posted on 2000-02-28
10
Medium Priority
?
559 Views
Last Modified: 2013-11-10
i HAVE A LX CHIPSET MOTHERBOARD with 64mb of SDRAM. I think it is the PC66 variety. My MB can be clocked up to 80 something Mhz.
Would it hurt the motherboard or existing memory if I bought PC100 memory  and ran it with my PC66 memory?
I would probably still run the MB at 66mhz.
0
Comment
Question by:prae
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
10 Comments
 
LVL 7

Accepted Solution

by:
frache earned 150 total points
ID: 2564361

No problem ...
You can use PC100 ram.
You can mix PC66 and PC100 ram.

Note : Ok, also with PC133 ram ...
0
 
LVL 32

Expert Comment

by:jhance
ID: 2564556
>You can mix PC66 and PC100 ram.

Not a true statement.

You can mix PC66 and PC100 RAM as long as you run the memory bus at the speed of the SLOWEST RAM installed in the system.
0
 
LVL 3

Expert Comment

by:boom23
ID: 2564562
But if you overclock at 80 something mhz, then you might have a problem coz one of your ram is pc66 mhz.
0
Are You Ready for GDPR?

With the GDPR deadline set for May 25, 2018, many organizations are ill-prepared due to uncertainty about the criteria for compliance. According to a recent WatchGuard survey, a staggering 37% of respondents don't even know if their organization needs to comply with GDPR. Do you?

 
LVL 7

Expert Comment

by:frache
ID: 2564719

More details :

-You can mix PC66 and PC100 ram if you still run the MB at 66mhz.

- 80 Mhz :
Make a try with PC100ram only, because you can have problem with processor or graphic card (-> PCI bus overclocked at 40 Mhz - 80/2 )
After, if everything is Ok ( test everything during 2 hours) , plug PC66 ram.
If you have problem, you can try to adjust ram parameters in bios.
0
 
LVL 32

Expert Comment

by:jhance
ID: 2564747
>- 80 Mhz :

>Make a try with PC100ram only, because
>you can have problem with processor or
>graphic card (-> PCI bus overclocked
>at 40 Mhz - 80/2 )


Again, you're confused.  On all motherboards the PCI bus clock is INDEPENDENT of the CPU and memory bus clock.

Where are you getting your misinformation?
0
 
LVL 7

Expert Comment

by:frache
ID: 2565348
WRONG :
"On -ALL- motherboards the PCI bus clock is INDEPENDENT of the CPU and memory bus clock".


Not agree with "ALL" ...

Many motherboard have PCI clock and AGP
clock synchronized with FSB clock (external processor clock). Particularly old motherboard with LX chipset ...
 
0
 
LVL 7

Expert Comment

by:sorgie
ID: 2565732
your not going to get any benefit from Pc 100 running at 66mhz and I really thing that trying the overclocking route with PC100 will if anything show no improvement and maybe just problems

stick with what your MB is designed for and save the extra expense.

Good Luck
0
 
LVL 6

Expert Comment

by:1cell
ID: 2565767
yes, the only benefit from running 100MHz RAM on a 66MHz bus is future upgradability.  Yes, it will work, but your 100MHz RAM will run at 66MHz.
0
 

Author Comment

by:prae
ID: 2566347
One of the reasons I asked is that PC66 SDRAM is harder to find and MORE expensive than PC100 SDRAM in New Zealand. I can also get a good deal on PC100.  :-)
I'm not one for overclocking but could try as I heard that some PC66 can run at faster speeds. I have a couple of settings before I get to the 80mhz bus speed.
But thats where I get confused. Is the bus speed linked to the memory speed?
I thought the bus speed and memory speed were linked.
0
 
LVL 7

Expert Comment

by:frache
ID: 2568116

- Memory speed is linked with FSB - Front side bus = External processor clock.

-> With FSB at 66Mhz, you can use PC66,PC100 or why not PC133 ram.
-> With FSB at 80 Mhz ,PC100 is ok, but you can have problem with PC66.
Sometimes nothing to do ( "good" PC66 support 80 Mhz ).
Sometimes you can "play" with Ram timings in bios.

- Cache memory (level 2 or 3) speed is linked with FSB.

- AGP and PCI bus :  

With Pentium and first generation( LX chipset)  of Pentium II motherboards, often AGP speed = FSB, and PCI speed = FSB /2.

With second generation of Pentium II motherboard  ( BX chipset ) , 2 ways :

synchronized : AGP speed = FSB, and PCI speed = FSB /2.

asynchronized : whatever FSB speed, AGP speed = 66 Mhz / PCI speed = 33 Mhz.

Sometimes a motherboard have a jumper or a bios setting to change this parameter ( synchronized / asynchronized)

Synchronized is generally better for performance ( no lose cycles ).

0

Featured Post

Get your Disaster Recovery as a Service basics

Disaster Recovery as a Service is one go-to solution that revolutionizes DR planning. Implementing DRaaS could be an efficient process, easily accessible to non-DR experts. Learn about monitoring, testing, executing failovers and failbacks to ensure a "healthy" DR environment.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

This is about my first experience with programming Arduino.
This article will show how Aten was able to supply easy management and control for Artear's video walls and wide range display configurations of their newsroom.
This course is ideal for IT System Administrators working with VMware vSphere and its associated products in their company infrastructure. This course teaches you how to install and maintain this virtualization technology to store data, prevent vuln…
Video by: ITPro.TV
In this episode Don builds upon the troubleshooting techniques by demonstrating how to properly monitor a vSphere deployment to detect problems before they occur. He begins the show using tools found within the vSphere suite as ends the show demonst…

656 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question