Hands-On Review: G3 PowerJOLT 400/200/1 MB

By Bill Fox
April 27, 1999

MacTell. Price: $645.99 street (BottomLine)

Pros: Overclockable, stable at fastest settings, great cache control software

Cons: Minimalist documentation, switches difficult in 9600, defective PCI slot notch

Rating: 4 out of 5 Exclamation Points: ! ! ! !

Brought to you by Macs Only! Copyright 1999 by Bill Fox

MacTell came up on my radar screen as a Mac clone builder in 1997. When Apple ended licensing of the Mac OS, MacTell diversified into CPU accelerator cards and graphics accelerator cards, bringing the speedy Ticket-to-Ride graphics chip to the Mac. Now MacTell has further diversified into accessories for the iMac, the iMaccessories line.

MacTell is now best known, perhaps, for its line of G3 CPU upgrade cards, the G3 PowerJOLT. It comes with a PCI connector for most PowerMacs and clones, a ZIF connector for recent Apple G3s and a ZIF connector for UMAX 500/600s. The G3 PowerJOLT 400MHz with 1 MB of backside cache running at 200 MHz (PJ400) is the top of the line for PCI PowerMacs.

A PJ400 was loaned to Macs Only! for this review.

What You Get

The PJ400 came in a sturdy box with foam padding so the card is well protected during shipping. Besides the card, there was a floppy disk and a manual.

The PJ400 card, shown above and at right, has a rather large heat sink with an auxiliary fan. I did not remove the heat sink to see the cache specs or to determine whether the CPU was manufactured by IBM or Motorola. The card itself is a tall card but there is a clear area about an inch from the top so it may be trimmed by a professional for a low profile case if necessary. The fan, shown at the left, is unique among G3 cards with such large heat sinks.

The PJ400 has two dial switches, one to change the system bus clock speed and the second to change the ratio of the CPU to bus clock speed.

The disk comes with the excellent PowerJOLT control panel, PowerJOLT extension, a preliminary .pdf file PowerJOLT Installation manual, a preliminary .pdf file on the PowerJOLT control panel, a licensing agreement and a Netscape icon that opens to MacTell's page on the 400.

The control panel, shown at right, is one of the best in the business but clearly the coolest looking. It reports on the speed of RAM, whether motherboard cache is on or off, the G3 type, CPU speed, cache size, bus speed, cache speed, CPU to cache speed ratio and CPU temperature.

The printed installation guide is minimal with 6 pages and one of them is blank and another spells out the warranty. Still it has the fundamentals and no one should have difficulty installing the PJ400 in the right spot. There are diagrams for the 7500/7600, 85/9500 and 86/9600 families. There's a half page on troubleshooting the usual problems. It recommends downloading and installing Libmoto. MacTell offers a 2-year limited warranty.

There's also a "green sheet" set of installation instructions that covers the installation steps, use of the Control panel and the switches on the PowerJOLT card. There are two tables for setting the two rotary switches on the PJ400, one for system bus speeds of 40-45 MHz and the other from 45.5-53 MHz.. One rotary switch controls the system bus speed (right) and the left one controls the CPU to bus speed ratio (3.0 to 8.0). The highest setting pair is 53 MHz for the system bus and 424 MHz (ratio=8) for the CPU. It came set at 50/400. The switches, shown at left, look substantial and they are but their placement and design is not the best. They are located about an inch down from the top edge of the card (this allows the card to be trimmed for a low case) and face 90 degrees out from the plane of the card (sideways) rather that facing the upper edge or out. This makes it hard to adjust them when the card is in place for many systems, including my 9600.

Installation And Use

Everyone should know something about installing CPU daughter cards by now so I am going to be brief. First the control panel and extension are installed and the computer shut down. Then the old card is simply lifted straight out of the daughtercard slot on the motherboard with minimal rocking motion to avoid damage to the slot. This is usually a little tough to do the first time. Finally, the new G3 CPU card is carefully aligned and pressed straight into the daughtercard slot until fully seated. It is usually recommended that the motherboard cache be removed if possible.

The test computer is configured as follows:

Apple PowerMac 9600

• PowerLogix PowerForce G3 250 running at 300 MHz
• 1 MB cache running at 200 MHz
• System Bus 50 MHz
• 128 MB RAM
• MacPicasso 540/3D Overdrive 3Dfx graphics accelerator card
• Mac OS 8.5.1
• Libmoto enabled
• Virtual Memory off

In the case of the PJ400, it was extremely difficult to push it down all the way into the slot in my 9600, the hardest that I had ever experienced. I kept pushing though and it got far enough in to allow the computer to boot up. This was a mistake. Removing the PJ400 after all the tests was even more difficult than installing it. I had to rock it quite a bit to dislodge it and ended up breaking off the top of the crosspiece in the slot that fits into the notch on the PJ400. Apparently, the card sent me for review had a manufacturing defect that resulted in the notch being too narrow. This problem is being looked into and rectified by MacTell as needed.

The PJ400 was set to its maximum CPU speed, 424 MHz, with its maximum system bus speed of 53 MHz. The backside cache ratio could not be increased beyond 2:1 without getting a freeze so it ran at 212 MHz. The PJ400 was run in this configuration for several weeks without encountering any stability problems.

A series of tests comparing the PJ400 with the PowerLogix PowerForce 250 (running at 300/200/50) were run. The PJ400 was set at its default settings (400/200/50) and at its fastest settings (424/212/53), where the convention is CPU/Cache/Bus Speeds.

The CPU and FPU speed of the MacTell PowerJOLT 400 at 424 MHz is about 40 per cent faster than the PowerLogix PowerForce at 300 MHz, about the same ratio as their CPU clock speeds. Unfortunately, it seems that the MacPicasso graphics cards were more or less saturated by the PowerLogix card so no performance increase was obtained with the faster MacTell card.

Conclusions

The MacTell G3 PowerJOLT 400 is an excellent CPU upgrade card. It has dials to overclock its rating by 6 per cent, thereby gaining a speed advantange over its fixed-speed rivals. The PJ400 has a large heat sink and CPU fan which is unique among G3 cards. It ran rock stable for several weeks at its highest setting. Its cache control software is second to none, actually really terrific. The documentation is minimalistic. The speed switches are harder to use than on some other cards. The review card had a serious manufacturing defect, a slot notch that was too narrow, which was either bad luck or a simple defect that I expect MacTell has rectified. At $646, the MacTell PowerJOLT 400 is a great buy, especially for those who have not yet upgraded their PCI Mac and clones to a G3.

. . [Macs Only!]