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
Solved

CPU Pin21 on Pentium II

Posted on 1998-06-10
8
231 Views
Last Modified: 2010-04-26
According to Tom's hardware guide (tomshardware.com/Celeronto100.html) you can get all 66 MHz Slot 1 CPU's to run at 100 MHz on a BX board by simply covering the B21 pin on the P-II's connectors.
I've heard that Intel changed this, and ships the newer P-II's with a safeguard against taping off the B21 pin. Can anyone tell me if this is true? Are the newer P-II's "fixed" to keep overclockers from hiding the B21 pin??
 
0
Comment
Question by:reetkever
  • 5
  • 2
8 Comments
 

Author Comment

by:reetkever
ID: 1136023
Edited text of question
0
 

Author Comment

by:reetkever
ID: 1136024
Edited text of question
0
 

Author Comment

by:reetkever
ID: 1136025
Edited text of question
0
Use Case: Protecting a Hybrid Cloud Infrastructure

Microsoft Azure is rapidly becoming the norm in dynamic IT environments. This document describes the challenges that organizations face when protecting data in a hybrid cloud IT environment and presents a use case to demonstrate how Acronis Backup protects all data.

 
LVL 32

Accepted Solution

by:
jhance earned 100 total points
ID: 1136026
First, not ALL PII will work at 100MHz.  If you read what "Tom" says, you'll see that some will and some won't.  

It is true that some of the PII chips are now being shipped by Intel with the connection from pin 21 on the conector to the CPU removed.  This will keep you from "casually" trying to cover pin21 and overclock.  A determined user can still do it, however, as all you have to do is remove the plastic case and connect the pin to the CPU with a jumper.  Of course, it help to be handy with a soldering iron.  At this point, it's not exactly clear which PIIs are "neutered" by Intel and which are not so it may take some trial-and-error and/or visual inspection to verify what you have.  As more data becomes available, it may be possible to determine by date code or rev level.
0
 
LVL 9

Expert Comment

by:larbel
ID: 1136027
Save yourseft the trouble...  Buy an Asus or Abit board which will let you manually run any PII at up to 133 FSB.
0
 

Author Comment

by:reetkever
ID: 1136028
I'd like to thank jou for your answer, there's one more thing: You mentioned that on close inspection I could determine whether the B21 is "neutered" or not. Can I verify this without opening the cover (that is *before* I decide to buy) or does the cover has to be opened?
0
 
LVL 32

Expert Comment

by:jhance
ID: 1136029
If you have a good DMM (digital multi-meter) you could determine if the pin is open or not.  Measure the resistance from pin21 to both the +VCC supply and to GROUND.  If you get infinite (or > 1MEG Ohm) then it's likely disconnected.  If it < 10K to either, then it's probably connected.

BTW, the plastic case just snaps off after you release the little plastic catches around the edge.
0
 

Author Comment

by:reetkever
ID: 1136030
I think I'm going to follow up on larbel's advice which will save me the hassle. Thanks larbel.
I want to thank jhance for sharing his knowledge.(where do you get all this information??)
Take care.

0

Featured Post

Free Tool: Site Down Detector

Helpful to verify reports of your own downtime, or to double check a downed website you are trying to access.

One of a set of tools we are providing to everyone as a way of saying thank you for being a part of the community.

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.
What do we know about Legacy Video Conferencing? - Full IT support needed! - Complicated systems at outrageous prices! - Intense training required! Highfive believes we need to embrace a new alternative.
Established in 1997, Technology Architects has become one of the most reputable technology solutions companies in the country. TA have been providing businesses with cost effective state-of-the-art solutions and unparalleled service that is designed…

809 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