1 00:00:00,000 --> 00:00:05,160 One of the things people got outright angry about when the now-canceled RTX 408012 gig 2 00:00:05,160 --> 00:00:12,160 from NVIDIA was announced was the memory bandwidth. A spec you might also see described as bus width, or something similar. 3 00:00:12,160 --> 00:00:19,080 But why exactly is it so important? Is it some ultra-wide wheeled vehicle that carries your data to and fro, assuming they 4 00:00:19,080 --> 00:00:23,640 have a permission slip? Well, actually, that questionable analogy isn't far from the truth. 5 00:00:23,640 --> 00:00:28,760 You see, a bus in computing is a general term for a data link between two components. 6 00:00:28,760 --> 00:00:33,920 For example, USB stands for universal serial bus, because it's supposed to be a do-everything 7 00:00:33,920 --> 00:00:41,200 connection for transmitting data. But in graphics card land, the memory bus connects the GPU itself to your card's video 8 00:00:41,200 --> 00:00:47,520 memory or VRAM. The basic way a graphics card works is that the GPU, which you can see here, acts upon 9 00:00:47,520 --> 00:00:52,480 data stored in the VRAM, which are these little modules, to generate the images you see on 10 00:00:52,480 --> 00:00:57,680 your screen. Among other things, VRAM contains the textures that make the objects on your screen look like 11 00:00:57,720 --> 00:01:01,160 they're supposed to, as well as data used to create visual effects. 12 00:01:01,160 --> 00:01:05,960 The higher the resolution, texture quality settings, or VFX settings, the more VRAM 13 00:01:05,960 --> 00:01:10,800 your GPU will use, which is why you sometimes see people criticize NVIDIA or AMD when 14 00:01:10,800 --> 00:01:15,920 they pair a powerful GPU that could otherwise run games on high settings with an insufficient 15 00:01:15,920 --> 00:01:23,640 amount of VRAM. Unacceptable! And the more data that sits in VRAM, the wider memory bus you need to get that data to your 16 00:01:23,640 --> 00:01:28,880 GPU. But how do you read a spec sheet that gives a number of bits, or gigabytes per second 17 00:01:28,880 --> 00:01:32,640 for your memory bus, and how do you know if that number is high enough? 18 00:01:32,640 --> 00:01:37,400 So the bit width is just telling you how many bits the bus can move for each cycle of the 19 00:01:37,400 --> 00:01:42,320 memory clock. Basically, how much data is being moved per one hertz. 20 00:01:42,320 --> 00:01:46,560 Of course, seeing as how memory speeds on modern cards are typically well over a thousand 21 00:01:46,560 --> 00:01:49,800 megahertz, this adds up to quite a lot. 22 00:01:49,800 --> 00:01:56,000 For example, the top-end RTX 4090 has a bit width of 384 bits, but this translates into 23 00:01:56,000 --> 00:01:59,840 around 1 terabyte per second of total memory bandwidth. 24 00:01:59,840 --> 00:02:03,640 Now most of you aren't going to be buying a daddy warbucks-level graphics card, so 25 00:02:03,640 --> 00:02:07,880 how much does bus width matter as you go down the product stack? 26 00:02:07,880 --> 00:02:12,640 The answer is, not a whole heck of a lot, without additional context. 27 00:02:12,640 --> 00:02:16,960 Just like it's unwise to compare raw clock speeds between different generations of CPUs 28 00:02:16,960 --> 00:02:21,080 because their underlying architectures are so different, you can't simply look at the 29 00:02:21,080 --> 00:02:26,360 raw bus width for your VRAM and decide that a product is over or underpowered. 30 00:02:26,360 --> 00:02:32,000 It's not that simple. A good recent instance of this was the reaction to the 12 Gigabyte version of the NVIDIA 31 00:02:32,000 --> 00:02:37,040 RTX 4080 prior to Team Green pulling the plug on the card completely. 32 00:02:37,040 --> 00:02:40,760 Although the criticisms of the card being positioned as a 4080, despite the fact that 33 00:02:40,760 --> 00:02:45,040 it had lower-tier specs, were completely warranted, some of the anger at the memory 34 00:02:45,040 --> 00:02:53,520 bus specs had us raising an eyebrow. That first it seemed silly that the 408012 Gigabyte version was shipping with a 192-bit 35 00:02:53,520 --> 00:02:57,480 memory bus, narrower than the previous gen RTX 3070. 36 00:02:57,480 --> 00:03:03,040 However, with the higher power draws and thermal output of the Ada Lovelace GPU series, the 37 00:03:03,040 --> 00:03:08,600 408012 gig was to get a massive 48 megabytes of level 2 cache, which is extremely fast 38 00:03:08,600 --> 00:03:13,400 memory that sits on the GPU die itself and is separate from the main VRAM. 39 00:03:13,400 --> 00:03:17,520 This might not sound like much, but it's actually a huge leap from the 6 megabytes 40 00:03:17,520 --> 00:03:20,520 that the previous flagship 3090 Ti came with. 41 00:03:20,520 --> 00:03:25,520 The idea is that substituting VRAM bandwidth for cache is easier on your card's power 42 00:03:25,520 --> 00:03:30,040 and thermals, and we might see this become more common in the future as we try and squeeze 43 00:03:30,040 --> 00:03:34,520 more and more performance out of the GPUs themselves. Okay, so that was a lot. 44 00:03:34,520 --> 00:03:39,160 Here's our point. A wider bus and more memory bandwidth is better. 45 00:03:39,160 --> 00:03:44,880 That's true. However, as always, you can't rely just on the spec numbers when buying your next graphics 46 00:03:44,880 --> 00:03:50,040 card. Instead, read reviews and benchmarks and specifically look to see if there are reported problems 47 00:03:50,040 --> 00:03:54,200 with textures or visual glitches at higher frame rates and quality settings on cards 48 00:03:54,200 --> 00:04:01,880 that have relatively narrow memory buses. Prioritize a strong GPU and having enough VRAM and worry about memory bandwidth only 49 00:04:01,880 --> 00:04:08,160 if something seems off when looking at test results. Besides, there are already enough specs to keep track of anyway, like if the card you 50 00:04:08,160 --> 00:04:12,840 want will even fit in your case. Thanks, NVIDIA. 51 00:04:12,840 --> 00:04:19,000 And thank you for watching this video, earnestly. Like the video if you liked it, dislike it if you disliked it, check out our other videos, 52 00:04:19,000 --> 00:04:22,320 comment below with video suggestions, and there's one more thing I'm gonna ask you 53 00:04:22,320 --> 00:04:25,680 to do, okay? Can you subscribe and follow to TechWiki? 54 00:04:25,680 --> 00:04:28,960 Just this one time, okay? Just a little bit. Can we see if we can do that? 55 00:04:28,960 --> 00:04:29,960 Okay, thanks.