Learn about the technologies behind the Internet with The TCP/IP Guide!
NOTE: Using robot software to mass-download the site degrades the server and is prohibited. See here for more.
Find The PC Guide helpful? Please consider a donation to The PC Guide Tip Jar. Visa/MC/Paypal accepted.
View over 750 of my fine art photos any time for free at DesktopScenes.com!

[ The PC Guide | Systems and Components Reference Guide | Motherboard and System Devices | System Cache | Cache Structure and Packaging ]

Daughterboard Cache

Starting with the Pentium II processor (a.k.a. "Klamath") Intel has introduced a new form of packaging, called SEC (Single Edge Contact). The integrated cache of the Pentium Pro processors ran at processor speed and offered very high performance, but was very expensive to manufacture. The motherboard cache of the regular Pentium was easy and cheap to produce but offered lower performance. SEC is a compromise where the processor and cache are mounted together on a small "daughterboard" that plugs into the motherboard. This greatly reduces manufacturing costs, and also means that a bad cache chip doesn't result in the processor being wasted.

This type of cache runs at a faster speed than it would if it were on the motherboard, but slower than an integrated cache; this is why it is a compromise between the other two designs. On the Pentium II the level 2 cache runs at half the processor speed. So a 266 MHz Pentium II will have a 133 MHz level 2 cache. Not as good as the 200 MHz Pentium Pro's integrated cache, but a lot faster than running it at 66 MHz. The Pentium II's cache is also non-blocking, like the Pentium Pro's.

Note: Even though the Pentium II has an architecture very similar to that of the Pentium Pro, due to a design limitation it will only cache the first 512 MB of system memory. The Pentium Pro will cache up to 4 GB of system memory.

Next: Motherboard Cache


Home  -  Search  -  Topics  -  Up

The PC Guide (http://www.PCGuide.com)
Site Version: 2.2.0 - Version Date: April 17, 2001
Copyright 1997-2004 Charles M. Kozierok. All Rights Reserved.

Not responsible for any loss resulting from the use of this site.
Please read the Site Guide before using this material.
Custom Search