 When Nvidia bought out the defunct company 3dfx they acquired their patents and intellectual property including the trademark SLI name that had been used to describe 3dfx's system for using multiple graphics cards working together to achieve better gaming performance, but by the time they reintroduced SLI to consumers its underlying technology had undergone some very significant changes Let's see just what made the very first generation Nvidia SLI tick After this message from our sponsor that keeps Linus tech tips ticking Zotac's mech one PC is an ultra slim desktop that's built for gaming it features a sleek robotic style And you can check it out at the link below All right so in the late 90s 3dfx made a handful of now famous blunders first they decided to manufacture their cards themselves As opposed to just selling chips and providing reference designs to add in board partners But because their new factory couldn't compete on either quality or cost with Taiwanese and Chinese based AIBs OEM relationships that they had hoped would come never materialized To their focus on raw horsepower rather than modern features Allowed Nvidia to steal the market share crown from their flagship Voodoo 3 Then put the nail in their coffin with the GeForce 256 which arrived earlier to the market and was Vastly technologically superior to the delayed napalm core that they used in the Voodoo 4 and Voodoo 5 3dfx filed for bankruptcy in 2002 So then it only took two years for Nvidia to decide that selling two graphics cards rather than one per customer is Pretty cool and roll out SLI again Except that this time it stood for scalable link interface rather than scan line interleave This is because instead of having each card render alternating lines of a single frame Nvidia opted to use two new approaches to splitting the rendering load between the two cards In alternate frame rendering or AFR each card takes turns rendering a full frame this was the preferred method and typically resulted in the best performance scaling and in split frame rendering or SFR the 3d scene would need to be broken down Horizontally depending on geometry load with one card assigned to render the bottom part of the frame while the other handled the top now via both of these methods whether it was outputting half of every frame or alternating full frames the Secondary card would send its output to the upper or master card via the brand new 400 megahertz 1 gigabyte per second SLI connector then that top card would output the final image to the screen now it was this high bandwidth connection that gave Nvidia solution both its name and And it's high performance or well sometimes high performance You see without a software SLI profile the second card would remain either completely unused or even end up hurting performance and Because the system had no way of knowing on its own which SLI rendering settings would work best for a given game it was up to the driver team to hand validate both brand new games and some significant older titles So this process was more work than you might think and it wouldn't be until many driver updates later during the summer after launch That the green team would ship their 100th SLI profile now. Let's talk about the hardware During the first unveiling Nvidia was actually using a Xeon platform based on the 7525 chipset For its newfangled high-speed PCI Express expansion slots, but despite these demos being originally run on an Intel chipset Nvidia ended up requiring users to purchase a motherboard that was equipped with an SLI ready variant of Nvidia's own and force for chipset now the successful user modification of non SLI certified boards raised quite a few questions about whether this was an artificial limitation designed to help Nvidia maintain a foothold in the chipset market, but I digress The next thing you needed was a powerful CPU to keep both cards well fed with data So we're using an overclocked opter on that will give us similar performance to the fastest CPU at the time the single core 2.6 gigahertz FX 55 55 third a good 24 pin ATX power supply was strongly recommended Now the 6800 GTs that we have in here their TDP is only 67 watts and our whole system pulls only about 260 watts from the wall under load But there's more to a quality power supply than just wattage one having a suitable 12 volt rail distribution was absolutely necessary to keep it from just turning off when you fired up a game and two native PCI Express power connectors were a definite bonus at the time so you didn't have to use adapter dongles onto the cards themselves SLI technology required pretty much identical cards like this pair of matched XFX 6800 GTs and Initially even the BIOS revisions on the cards needed to be the same though that did Ease up over time to the point where even slightly mismatched cards would equalize according to the clock speeds of the slower card Finally a well ventilated case was a must most of the cases from this era used 80 millimeter cooling fans So especially given the poor design of the reverse blowing single slot cooler on our card It was common to see side intakes modified into cases after the fact like this one and Even with our extra airflow our cards hit a toasty 85 degrees under load Now let's look at performance Nvidia cited 1.87x scaling and synthetic benchmarks, but our own testing gave us 1.64 1.82 and 1.76 Though it should be noted that when it comes to real games we actually managed an amazing 1.98 percent scaling in Half-Life 2 and we saw up to 1.86 in Far Cry So in essence this tech when it worked Would enable you to step up to the next image quality and or resolution level and what's cool Is that the higher the load the better it scaled Furthermore unless it ran out of VRAM which does not add up between the cards It's it's cloned the system took games from the next-gen like fear Which was so demanding it initially shipped with a 1024 by 768 maximum resolution from Cinematically playable to actually playable and before you ask Yes Yes indeed it can at a mixture of medium to low settings this machine produced over 40 FPS at 1024 by 768 in a game that came out three years after this card launched Neat right? Now let's talk downsides and oh there were plenty the expense of a fast CPU SLI ready board and power supply aside alternate frame rendering introduced a temporal artifact known as Microstuttering where the frame rates were high, but some users reported choppy or jittery in-game animations and This tech lived and died by the existence of an SLI profile with some games Whether by design or due to just not getting around to it Never ending up working with SLI meaning that that second card that you bought Was a terrible value if your favorite game didn't end up scaling Furthermore there were some general quality of life issues including but not limited to the fact that two cards is louder than one changing SLI modes Required a system reboot at the start your second monitor would go black once a game was full screen And I had this bizarre issue with a Xurius BitTorrent client remember that where it and Firefox if they were running at the same time SLI would disable itself, but still show enabled in the control panel and the list kind of goes on so bottom line despite its first generation flaws SLI when it worked was so powerful that it exceeded Nvidia's next generation 7900 GTX's performance making it really freaking cool when it worked Speaking of working Squarespace is a great way to get a beautiful and working website They offer 24 7 support via live chat and email Plan started just $12 a month and you get a free domain if you buy Squarespace for the year and Every site includes tons of great features responsive design so it scales to look great on any device commerce Every website comes with a free online store their cover pages feature which allows you to set up a beautiful one page online presence in minutes and the ability to publish content in Apple News format directly from the Squarespace blog module So start a trial with no credit card required and start building your website today When you decide to sign up for Squarespace head over to Squarespace.com Slash LTT and use offer code LTT to get 10% off your first purchase. We're gonna have that linked below So thanks for watching guys Massive shout out to Benoit Pierre for sending us a working SLI motherboard for our test If this video sucked you guys you know what to do But if it's awesome get subscribed hit that like button or check out the link to where to buy the stuff We featured in the video description also linked in the description is our merch store which has cool shirts like this one and our Community forum which you should totally join. It is 5 10. I need to go do WAN Showdown