[Updates: Mac Voodoo3 drivers arrived in August 1999. See my www.mac3dfx.com site for more details and the related links below. In 2000, 3dfx announced retail versions of their Voodoo4 (single chip/32MB) and Voodoo5 (dual chip/64MB) would be available in summer 2000.

March 25th, 1999: A reader reported in the main site news that MC told him the SLI enabled drivers would be released next week. As all owners sadly know, that never happened. Also reported in the main site news in April was a reader comment that Microconversions said Mac Voodoo 3 cards would be available at the summer Macworld. But if you read the front page news regulary you know that some time later they said that Mac Voodoo3 silicon (to address the 565 pixel format issue I noted with the Banshee in my Interview with VillageTronic in Dec 98) would likely not be available until the end of the year. And of course MC later closed shop, reopening as iWonder. All this happened after the following editoral was written. -Mike]

Since the release of the Mac Voodoo2 Game Wizard last year, readers have often asked when SLI support (Scan Line Interlacing - two Voodoo2 cards working in parallel) will be available on the Mac. Only MicroConversions can answer that one for sure, but I wonder if it will even matter that much by the time it finally arrives. Why? With the Voodoo3 appearing this spring, which has better than dual Voodoo2 SLI performance (according to tests by PC sites and 3Dfx's own press release), fast 2D video (missing from the Voodoo2); SLI may not be very attractive for most Mac owners in comparison. The SLI cost in $$$ and slots is not trivial for all but the most hard core gamer, and they are also the most likely to buy a better performer if it is available.

To those that wonder if there will be a Mac Voodoo3 card from 3Dfx, I'm betting there will be. My sources recently whispered rumors of newly hired mac programmers (just a coincidence I'm sure ;-).

The fact the Voodoo3 performs better while using only one precious PCI slot, and provides stellar 2D video as well will hard for most Mac owners to ignore. Considering that most Macs have only 3 PCI Slots, how many owners will want to fill two of them with a 3d only/game only set of video cards? The total cost in dollars and slots may be too much for the benefit gained for many owners I suspect.

The other popular question I'm asked is if SLI will require that both Voodoo2 cards be Game Wizards? On the PC I've mixed brands of Voodoo2 cards in SLI mode with no problems (both have to be the same memory size), and even PC driver software that performed a card check (i.e. - the original Wicked 3D Voodoo2 drivers) ran fine with the 2nd card being a Creative Labs version (even Metrabyte states this is true).

Some time back when Game Wizards were very hard to find in stock, I had suggested that MC consider a 2nd Game Wizard model; a std PC reference design card which could have increased supply and lowered costs (as PC ref design cards are made by the hundreds of thousands). This could be an attractive (lower cost) option for existing Game Wizard owners if SLI mode is ever supported, since the monitor sense lines (the unique feature of the Game Wizard) are not required for the 2nd card. For those Mac owners with VGA monitors and video cards (even the new B&W G3 is VGA), the VGA connectors of the reference design card would eliminate the need for adapters or replacement cables as well.

Don't get me wrong, I still want to see SLI support on the Mac, but with the Voodoo3 due to be released soon, it does not have near the attraction for me now as it would have had last year. If a Mac Voodoo3 does arrive shortly after the PC version, there may be no incentive to even use SLI on the Mac from a consumer demand or performance standpoint in my opinion. However if Voodoo3 does not become available for the Mac, SLI would be the choice for hard core gamers that have the PCI slots and $$$ to spare.

How Much Faster is SLI?:
Remember that SLI mode performance varies by CPU speed and game title. Due to overhead and the fact there is literally no CPU currently available that can saturate a pair of Voodoo2 cards in SLI configuration, don't expect twice the performance of one card. The benefit seen in documented tests varies from none to about 85% best case. This is clearly shown in comparison tests done at sites like GameCenter.com [CPU Speed Results and Performance by Game Title and CPU Speed]. As shown in the table there, SLI performance increase ranged from none (some were actually a few % negative) to 85% depending on the game used.

The table below shows the PII 300 SLI Unreal TimeDemo results at various resolutions in Unreal. The Unreal PC multitexture patch was applied, but as the tests were run in September it was not the current version of Unreal of course. The purpose of this data is to show the boost provided by SLI, not to compare scores to other platforms or later versions of the game. A faster CPU would have shown better results, but the PII 300 delivered similar scores to my Game Wizard equipped Apple G3/300, currently in the high end of the installed Mac base anyone would agree.