processor upgrades Graphics Cards

G3/400 or G4/400? Two PowerLogix Upgrade Options Explored

Don Engstrom, Reviews Editor

Overview: Awhile back we reviewed the PowerForce G4/400 upgrade card from PowerLogix. This past Friday, PowerLogix announced the following new pricing across their upgrade line:

  • G3/300/150/1MB $299
  • G3/400/200/1MB $425
  • G3/500/250/1MB $735
  • G4/400/200/1MB $850

This pricing scheme may may raise a few eyebrows. Is it really worth paying twice the price to get a G4 rather than G3 processor? We asked PowerLogix to send us their G3/400 card (along with a few others that we will cover in the coming weeks) to help us answer this question. Both the G3 and G4 PowerForce cards sport a reduced form factor compared to their predecessors, as well as the competition. Both are cooled by means of a heat sink although the G4 upgrades make use of a fan mounted on top of the heat sink to further aid cooling.

Software Installation:PowerLogix provides their drivers on CD and include an emergency boot floppy as well. Also on the CD is LinuxPPC, which will appeal to some but likely not to most. Be sure to install the driver software first as this will enable the backside cache on restart and install important system patches. It is always a good idea to make sure you have the latest version of everything as well. The "G3/G4 Profiler Init" extension configures the card with the settings you have specified and enables the backside cache. The "Cache Profiler" control panel provides the usual array of feedback and control options as well as a few related to LinuxPPC if it is installed.

Hardware Installation: Due to its compact design, handling and installing the card was a little tricky. It was quite a challenge to avoid touching the card's circuitry as there is little unused space on the card. Both Sonnet Tech and XLR8 place extension bars on their cards giving you an easy and safe place to work from. Other that this minor quibble the process was straightforward. The manual includes clear instructions for all of the supported machines. Eight dip switches on the card allows you to adjust the the card's speed. In a nice touch, PowerLogix pastes a chart of possible dip switch settings on the back of the card for quick reference. The switches are strategically located so they can be reached and adjusted without removing the card from the processor slot. This is especially helpful if you plan on experimenting with different settings to push the card's performance.

Performance/Stability: The G3/400 is a strong performer and, with two exceptions, manages to keep up with its big G4 brother on non-AltiVec savvy applications. The G4 is stronger in FPU functions as reflected in the scores below. The other big advantage of the G4 is, of course, the presence of the AltiVec instruction set. Users of Photoshop 5.5 may still want to consider the G4 option (yes, even at its higher price) as the speed of many operations can be increased by up to 300%.

We overclocked the G3/400 up to 440MHz while maintaining a 2:1 (220MHz) backside cache ratio. At this setting the card managed to trounce the G4/400's processor score! In our review of the G4/400 we were able to overclock that card to 450MHz but had to reduce the backside cache to 180MHz (5:2 ratio) to achieve stable operation. This, of course, caused a performance hit over the faster 2:1 ratio. At both 400MHz and 440MHz the G3 PowerForce seemed rock solid and ran all of our applications without a hitch.

Test Machine Configuration

Our test machine was a 9500 with 96MB RAM and OS 9 installed. We tested with an extension set comprised of all OS extensions plus those installed by PowerLogix. For the MacBench tests virtual memory was turned off and disk cache was set to 512k. These settings are consistent with those used on the MacBench base reference machine, a beige G3/300. For the real world tests we turned virtual memory on and set it to 97MB. We have included scores from past and upcoming PowerLogix card reviews to provide some additional context for the G3/400 card.

Product: PowerForce G3/400/200/1MB
Company: PowerLogix
Rating: (5 possible)
Hits: Excellent price/performance ratio & stability, can be overclocked to 440MHz without breaking a sweat, easy access to dip switches, 3 year warranty.
Misses: Small size and lack of extension bar makes it awkward to install.

MacBench 5.0 Scores

MacBench 5.0 is a subsystem-level benchmark that measures the performance of a Mac's processor, disk, and graphics subsystems to name a few. MacBench normalizes all scores relative to the base machine, a Power Macintosh G3/300. The base machine receives a score of 1000. For all MacBench tests, higher numbers mean better performance. For more detailed information on MacBench click here. Remember, MacBench 5.0 came out well before the G4 processor and was consequently not written to take advantage of or test the AltiVec (AKA Velocity) instruction set.




"Real World" Tests
(Shorter bars are better)

Time to Scroll a 574 page AppleWorks document from top to bottom.

Using the same document as above we did a search/replace command to replace the word "the" with the word "macbench," over 12,900 occurrences total!

Photoshop 4 "Real World" Test Results

All scores are relative to the stock 9500 which was assigned a score of 100. Lower numbers and shorter bars are better. Bear in mind that we didn't use a "Velocity/AltiVec" plugin for the G4 tests as neither PowerLogix nor Adobe provides one for this version of Photoshop. Adobe, however, has made their AltiVec plugin available for version 5.5. You should see about a 300% performance increase with certain filters in Photoshop 5.5 when using the G4







Render Boy 2.2.0

Time to render "Pool Table" example file

SoundJam MP3 Encode

Time to encode a CD track 4 minutes 26 seconds in length. Scores represent time rounded to the nearest second. SoundJam makes use of the G4's AltiVec instruction set.

Manufacturer -Card


Cooling System

Variable/Fixed Clock Rate

Tech Support


PowerLogix PowerForce G3/400/200/1MB PCI Heat Sink Variable Toll Free Phone
3 Years