Gadgetory

welcome back to hard Rome boxed I spent a fair bit of time over the last year or so exploring the world of external GPUs in fact just a couple of weeks ago I published my review of the latest gigabyte rx5 rated gaming box but this whole time I've been testing each GPUs and exploring how they perform I just can't shake the thought that they just aren't very good and in most circumstances don't make a lot of sense to buy the whole idea behind external GPS is a good one in theory you can plug in an external graphics processor to a system that has a weak GPU and immediately get gaming grade graphics performance this makes AGP you sound like a fantastic option for those that have an ultrabook with integrated graphics or just want a super portable gaming setup after all each GPUs are generally quite compact and designed as an add-on to slim light systems while this is a great theory and an idea that I think has a lot of potential right now a GPUs don't work like this in practice there are a bunch of fundamental flaws to the technologies that facilitate external graphics and that makes current generation products either poor value or just not a good option over alternatives for PC gaming almost all the blame goes to Thunderbolt 3 it's a super fast interconnect and great for attaching high-speed storage devices high resolution displays and other peripherals that require fast data transfer rates but it's just not fast enough for GPUs Thunderbolt 3 presents bandwidth and latency limitations that choke the living daylights out of a graphics card forming the single largest bottleneck for any a GPU equipped system the wayy GPUs work is they utilize Thunderbolt threes four lanes of PCI Express 3.0 so the GPU can connect and operate over familiar protocol a cursory glance would suggest the maths checks out to Thunderbolt 3 is a 40 gigabit per second protocol and pcie 3.0 x 4 requires just 31.5 gigabit per second however this does not take into account several key differences between Thunderbolt 3 and Raw PCIe Thunderbolt 3 operates through the chipset so it's not a direct connection to the CPU like the standard PCIe lanes used to connect a GPU in a desktop system on top of that there is typically an additional Thunderbolt controller at both ends of the cable when you factor in all these additional steps and chips between the CPU and GPU and the added protocols of Thunderbolt 3 you don't get anywhere near 40 gigabit per second of bandwidth for the GPU the bandwidth left for the GPU typically sits between 17 and 21 gigabit per second in a real-world memory copy test compared to 26 gigabit per second for direct to cpu pcie 3.0 x 4 that's roughly 30% more bandwidth from a direct connection and let's not forget that we're talking about just pcie 3.0 x 4 here not the full x 16 you'd get from a desktop slot we know from tech power ups previous testing that a gtx 1080 running over a pcie 3.0 x 4 interface will be kept to about 96 percent of its full time 16 performance so when you can't bandwidth by a further 25 percent or so next to Thunderbolt 3 more of that performance of roads but bandwidth is only one part of the story the real killer is latency when you add in the chipset Thunderbolt 3 controllers and the length of the cable itself there's a massive uptick in communications latency between the GPU and other components in a desktop PC the GPU is physically situated very close to the CPU and communicates over direct PCIe lanes that's not the case at all with EGP is where the GPU connects through the chipset and data is transmitted over longer cables the bandwidth limit but more importantly the added latency caps any eg PS performance to rents 70 to 80 percent of what the GPU inside is actually capable of when packed into a true gaming desktop or laptop and it doesn't matter whether the AGP use the gtx 1060 or gtx 10 atti any GPU placed into a Thunderbolt 3 enclosure immediately loses about 20% of its performance in the best-case scenarios and in the most latency impacted games like prey the performance hit is more like 50 percent or greater and when you start asking Thunderbolt 3 to do more on top of transmitting data to and from the GPU for example using the included USB or Ethernet ports on some EGP enclosures you start running into issues because there's just not enough bandwidth you'll either experience a performance hit and stuttering in games or the USB port simply won't work or cut out at random times and you especially shouldn't pass a display signal from the GPU back through the thunderbolt three cable to your laptop's built-in display this is a supported feature of a GPUs but again the lack of available bandwidth to send the return display signal leads to a noticeable performance loss in games this means that to get the most out of your a GPU you need to hook up an external monitor directly to one of the GPUs display outputs and for those that don't already have a monitor it's an added cost on top of the e GPU purchase price as it stands right now Thunderbolt 3 is just not suited to external graphics technologies it imposes far too many restrictions on bandwidth latency and attached devices such that it limits the performance and usability of external GPU enclosures to make these sorts of enclosures worth the time money we really need a next-gen connector technology something like Thunderbolt 4 with double the bandwidth and most importantly a significant latency reduction the next-gen Thunderbolt is probably a fair way away but if it can provide an earful PCIe x 8 connection with latency much closer to a desktop PC a GPUs wouldn't have anywhere near as high performance penalty and overall that make much more sense now you might be wondering what about those direct PCIe adapters you can buy the transform an m dot 2 slot or a mini PCIe slot into a full PCIe x 16 slot running it for time speeds in this case for its tone GPUs well these are better in theory as they provide a more direct connection but in practice they are not particularly plugin players you need a cable dangling out of your exposed laptop also Steve bought one and couldn't get it to work with several different laptops there seems to be a few compatibility issues there at the moment the other issue with a GPS is their price when you factor in the performance and a GPU delivers relative to its cost buying an a GPU makes very little sense for most people compared to other ways of getting gaming capable systems let's say you want a system capable of playing basic games like fortnight overwatch or csgo and you don't want to spend a boatload of cash if you go to the e GPU route you'll need to spend at least $200 on the enclosure and then grab a GPU like the GTX 1050 which these days cost around 150 dollars so all up the EGP use costing you 350 bucks and then on top of that you need a laptop with Thunderbolt 3 and an external display now when you factor in the performance penalty of using an e GPU through Thunderbolt 3 that gtx 1050 is going to fall closer to in videos popular integrated GPU the MX 150 the e GPU will probably be around 10 to 20 percent faster but the MX 150 is still capable of playing games like Fortnight on medium level quality presets realistically there's not much point buying the GTX 1050 EGP you if you have an MX 150 or greater discrete GPU so it's only worth buying for those that are stuck with integrated graphics and even then you need to already have a Thunderbolt 3 equipped laptop with that integrated graphics to consider buying this a GPU combo if you don't have that laptop my advice would be to buy a laptop with a discrete GPU inside either the MX 150 or preferably a true gtx 1050 Thunderball 3 laptops are already in the upper end of pricing and there are plenty of nice thin and light options with the MX 150 or even up to a GTX 1050 Ti inside it is similar price point if you want that sort of entry-level to midtech gaming experience in a portable form factor there's not much point buying a laptop plus a GPU when gaming capable portable laptops already exist higher-end discrete GPU snake even less sense if I'm honest take the Auris gtx 1070 gaming box which retails for 600 us with the Thunderbolt 3 penalty you're looking at performance around or below the level of a gtx 1066 gigabyte gaming laptop considering you already need an external display to get the best EGP performance why buy one at all over a complete and fully upgradable gaming desktop even on the budget here is a basic gaming system I made for around $600 that includes a quad-core Rison 320 200 G CPU a gig of ram and a GTX 1063 gigabyte this PC will perform about as well as the e GPU hooked up to a laptop sporting Thunderbolt 3 except it's a full gaming system the EGP requires a laptop to function so you'll either need to already have a compatible laptop or you'll need to buy one on top of the $600 asking price for just the EGP you it's a no-brainer to build the desktop if you don't already have a compatible laptop but II then if you do already have one of the compatible laptops buying a desktop PC over Annie GPU gives you much greater scope for upgrades in the future without compromising on performance for gaming right now now of course for some people that want portability and a compact set up a full gaming desktop isn't going to be what you're after but even if portability is your chief concern it makes more sense to buy a proper gaming laptop GTX 1060 laptops are available for below $1000 these days which is again less than the cost of a Thunderbolt 3 laptop plus a GTX 1070 GPU and you'll be getting better performance anyway the only reason I could see any GPU making sense is if you meet several very specific criteria you'd need to already own a slim and light laptop with Thunderbolt 3 that doesn't have a powerful discrete GPU and you need to be unwilling to purchase a similarly priced and arguably more powerful gaming desktop because you want the portability of an e GPU configuration you'd also need to be unwilling to ditch your existing laptop for a portable gaming laptop or unwilling to buy a second laptop for gaming for just a few hundred dollars more than an a GPU if you don't already own a laptop or if you're thinking of upgrading from something incompatible with a GPS for example if it doesn't have Thunderbolt 3 my advice would be to buy a fully integrated system that meets your gaming needs rather than an eg PU that's either a full gaming desktop in addition to whatever laptop you want as I've described previously or just a laptop with an appropriate discrete GPU inside there are plenty of options on the market for those that want entry-level experiences all the way up to powerful desktop grade hardware and often it'll be cheaper than buying an e GPU on top of a laptop without discrete graphics even though I don't recommend an H GPU for most buyers I still think the concept has some merit and could be a decent option once the technology matures if you could buy a cheap enclosure that uses a next-gen Thunderbolt technology allowing the GPU inside to provide its full desktop class performance it would be a neat way to upgrade a laptops graphics with that needing to buy a whole new system that was the goal of these thunderbox re enclosures but unfortunately it'll be a while before it becomes a genuine reality anyway that's it for this video on GPUs let me know your thoughts on external graphics in the comments but I'm really interested here what you guys have to say on this sort of technology at the moment don't forget to subscribe for more awesome content consider supporting us on patreon to get access to exclusive discord channel and I'll catch you next time