Mac Musings

The Celeron Effect

Dan Knight - 8 June 2000 - Tip Jar

Once upon a time Intel created a cheap version of the Pentium and named it Celeron. It had no level 2 (L2) cache, and it sucked. Thus was born the Celeron A, the same basic CPU, but this time with a 128K on-chip L2 cache. The cache runs at full CPU speed, making the Celeron more efficient than the Pentium III (with a 512k half-speed cache) at the same clock speed.

Intel doesn't advertise that fact. They want to sell more of the expensive processors, but Wintel and Linux geeks looking for the most bang for the buck are buying Celerons. If we ever buy a PC for home (our home schooling software requires Windows, although we find Virtual PC satisfactory at present), it's the way I'd go.

The New G3s

PowerPC 750CXIBM announced the PowerPC 750CX and 750CXe this week, the next generation of the PowerPC 750 that Mac users know as the G3 processor. I don't know if they plan on calling it the G3+, but I think they should.

Advantages of the 750CX and CXe include:

  • IBM copper and SOI technology allows 0.18 micron design
  • lower power consumption, 4W at 400 MHz
  • faster processor speeds: 350-550 MHz for the CX, 500-700 MHz for the CXe
  • runs at up to 10x motherboard speed
  • less expensive to implement

The 750CXe has the potential to run at 666 MHz on beige G3s, 1 GHz on blue ones. As far as upgrades for earlier Macs and clones, the 10x multiplier could result in speeds ranging from 333 MHz to 600 MHz. This can help close the perceived MHz gap between today's 500 MHz Macs and a handful of expensive 1 GHz Windows boxes, although it's only a single step toward closing the gap. On the other hand, if IBM moves to 0.15 micron technology, as used by Motorola in the G4, we can expect even higher chip speeds.

The on-chip L2 cache has two significant advantages over the external caching used with the G3 and G4. First, it's fast. As Intel users have discovered, a small but fast cache can outperform a large but slow one. We're about to experience the same thing.

The other advantage is that the faster cache eliminates the need for an external L2 cache. With a price of $77 (10,000 units at 350 MHz) and no need to buy and install a cache, the next generation iBook, iMac, and PowerBook should offer a good deal more performance with no increase in price.

In terms of overall performance, there are no Mac-based benchmarks yet. However, both IBM and Motorola have CPU specifications on their sites, making it possible to compare the G4/450 to the 750CX/450 on industry standard tests. The G4 scores approximately 21.4 on the SPECint95 benchmark, while the 750CX has a base performance of 18.0 (19.2 peak). The G4 is almost 20% faster at integer math.

The other popular test is SPECfp95, which measures floating point performance. Here the G4/450 scores roughly 20.4, while the 750CS has a base of 12.5 and a peak of 12.8. In this instance, the G4, which has two floating point units, is about 60% faster than the G3.

The other commonly used rating is MIPS, or million instructions per second. Motorola rates the G4/450 at 825 MIPS, while IBM claims 1,044 MIPS for the 750CX/450. Advantage G3+ by about 25%. (For comparison, the original Macintosh of 1984 ran at 0.7 MIPS - today's Macs are up to 1,500 times faster! The "wicked fast" Mac IIfx of 1990 scored 10.0 MIPS; today's iBook is about 50 times more powerful.)

Of course, these are theoretical benchmarks. What we really want to know is how well does it perform in Photoshop, how quickly can it crunch a work unit for SETI@home, and how will the new chips compare in the real world to the old G3 and current G4.

Time will tell. My biggest question is who will be first to ship a 750CX: Apple, Newer Technology, XLR8, Sonnet Technology, Powerlogix, or someone else.

In the end, I think we'll all be very happy with IBM's latest version of the G3. But if the 700 MHz version is available immediately, Intel won't be. LEM

I've received a number of emails informing me that the Coppermine Pentium III uses a full-speed 256k on-chip L2 cache. This doesn't change the fact that the Celeron A held its own against the earlier Pentium III. If anything, it validates the importance of a fast cache, which I see as the key improvement in the PowerPC 750CX and CXe. dk

Join us on Facebook. Follow us on Twitter.

Dan Knight has been using Macs since 1986, sold Macs for several years, supported them for many more years, and has been publishing Low End Mac since April 1997. If you find Dan's articles helpful, please consider making a donation to his tip jar.

Recent articles by Dan Knight

Links for the Day

Recent Content on Low End Mac

Recent Deals

About LEM Support Usage Privacy Contact

Low End Mac is an independent publication and has not been authorized, sponsored, or otherwise approved by Apple Inc. Entire Low End Mac website copyright ©1997-2012 by Cobweb Publishing, Inc. unless otherwise noted. All rights reserved. Apple, the Apple logo, Macintosh, iPad iPhone, iMac, iPod, MacBook, MagSafe, Mac Pro, Apple TV, and AirPort are registered trademarks of Apple Inc. Additional company and product names may be trademarks or registered trademarks and are hereby acknowledged.
  Advice is presented in good faith, but what works for one may not work for all. Please report errors to .
  LINKS: We allow and encourage links to any public page as long as the linked page does not appear within a frame that prevents bookmarking it.
  Email may be published at our discretion unless marked "not for publication"; email addresses will not be published without permission, and we will encrypt them in hopes of avoiding spammers. Letters may be edited for length, context, and to match house style.
  PRIVACY: We don't collect personal information unless you explicitly provide it. For more details, see our Terms of Use.

Custom Search

Share

Follow Low End Mac on Twitter
Join Low End Mac on Facebook

Low End Mac Reader Specials

Quantcast

TypeStyler 11 is now in the Mac App Store!! -- Special Introductory Price of $59.95!! -- To Buy From The Mac App Store Click Here Now!! Or buy direct from Strider Software.

Quantcast

Quantcast

Quantcast

Poker Mac Don't install Parallels to play poker online! Poker Mac will show you how to download and install a native Mac poker and Mac Casino applications in minutes.

Quantcast

Quantcast

Quantcast

Quantcast

Favorite Sites

MacSurfer
Cult of Mac
Shrine of Apple
MacInTouch
MyAppleMenu
InfoMac
The Mac Observer
Accelerate Your Mac
RetroMacCast
PB Central
MacWindows
The Vintage Mac Museum
DealMac
Deal Brothers
Mac2Sell
Mac Driver Museum
JAG's House
System 6 Heaven
System 7 Today
the pickle's Low-End Mac FAQ

Affiliates

Amazon.com
The Apple Store
The iTunes Store
PC Connection Express
GainSaver
Parallels Desktop for Mac
eBay

Low End Mac's Amazon.com store

Advertise

All of our advertising is handled by BackBeat Media. For price quotes and advertising information, please contact at BackBeat Media (646-546-5194). This number is for advertising only.

Open Link