If you’re anything like us, then the graphics card is your favorite part of a computer. Graphics cards let your computer do awesome things like super complex computations, physics processing, and most importantly, producing shiny graphics in games.
所以呢是一张图形卡，您如何弄清楚应该购买哪一个？
图形卡基本上是计算机内部的迷你计算机。它由图形处理单元（GPU）组成，并支持硬件，包括其自身的电源，RAM和HeatSink。
Similarly to how the CPU is the brain of the computer, the GPU is the brain of the graphics card. The GPU是专业人士electronic circuit旨在快速操纵和改变记忆以加速图像的创建。
简而言之，它可以在您的屏幕上制作这些漂亮的图片。
当人们想到GPU时，他们通常会想到两个主要制造商：Nvidia和AMD。英特尔是第三个GPU制造商，因为它们将GPU集成到了CPU中。还有许多其他制造商为手机，平板电脑和嵌入式系统制造GPU。
但是出于我们的目的，我们将讨论离散的GPUs, meaning the dedicated graphics cards you buy if you want to do really fun stuff with your PC. When it comes to discrete graphics cards, the two big names are NVIDIA and AMD.
在我们的办公室里，我们从AMD的《 200》系列中拿出了两张图形卡。我们有Radeon R7 270X和R9 290。
AMD和NVIDIA均每一到两年都会推出新一代的图形卡。每一代，他们都会在各种电源水平和价格选择方面提供许多不同的卡。让我们仔细研究一下，以便我们可以讨论一些重要的数字，以帮助您比较图形卡。
First, let’s discuss the R7 270X. It has 2 GB of video RAM, 1,280 stream processors, and a clock speed of 1,050 megahertz. It’s currently considered a solid mid-range graphics card.
Next, the R9 290. It has4视频RAM的GB，2,560个流处理器和947 Megahertz的时钟速度。目前，这被认为是中高范围的图形卡。
So, video RAM, stream processors, clock speed… what do these numbers all mean? Should you understand the specs, or just go with the most expensive graphics card you can afford?
Generally speaking, the best way to decide the right graphics card for you is to look at real-world gaming benchmarks, but we’ll get that in a few minutes. For now, let’s talk specs.
首先，视频公羊，也称为VRAM。通常，这是您在购买视频卡时会注意到的第一个规格，这通常是人们真正注意的唯一规格。这是一个错误，因为虽然VRAM是必不可少的，但拥有超出您所需的超过您的性能并没有提高性能。
Video RAM is mainly important for loading the textures and images that make up the game you’re playing on your screen. All of that data takes up VRAM, and it gets especially taxing on VRAM as you increase your game resolution, which we’ll also touch on in a minute.
如果您的游戏开始加载比VRAM可以处理的更多数据，则PC将额外的数据移至普通RAM。
分享很棒，对吗？好吧，并非总是如此。在VRAM试图与System RAM共享数据时，共享是不好的。
Any time you’re playing a game and your graphics card runs out of available VRAM, it causes huge hits to performance. If you’ve ever been playing a game that turns in – to – slide – show – mode, your graphics card may not have had enough VRAM.
有一些因素特别影响您的VRAM分配：分辨率，反陈述和质地质量。基本上，这些设置越高，您将需要的VRAM越多。这就是为什么高端卡包装大量VRAM的原因。如果您甚至想以4K分辨率考虑游戏，那么您将需要很多VRAM。
Oh, right. We should probably talk about resolution.
Every computer display is made up of tiny elements called pixels. Your resolution determines the number of pixels that will appear on your screen. More pixels equals more visual detail, resulting in crisper, clearer images.
Here’s a size comparison of common computer resolutions:
现代PC游戏的标准分辨率为1920×1080，通常称为1080p。对于稍大的像素计数，越来越流行的分辨率为2560×1440或1440p。目前，在消费级计算机屏幕的分辨率上方为3840×2160，或超高的定义4K。您可能可以从这个视觉效果中分辨出4K分辨率包装的四倍于1080p的四倍，从而大约是玩PC游戏时图形卡的需求的四倍。
在像4K这样的分辨率上生产大量的游戏像素需要大量的VRAM，这意味着您将需要一张高端图形卡以4K分辨率播放。In short: 2 GB is enough to play most PC games at 1080p, 4 GB is better for playing really demanding games at 1080p or most games at 1440p, and you’ll probably want 6 or more GB of VRAM to even attempt a demanding PC game at 4K resolution, unless you don’t mind your framerate resembling a slideshow.
这些只是粗略的准则。较新的，更快的内存技术，例如高带宽内存或HBM，将有助于减轻未来对更多内存的需求。
流处理器（AMD）或者库达核心（nvidia）are the processors in the GPU that perform the computations to produce images on the screen. They can also be used to do other types of complex mathematics and number-crunching, such as mining cryptocurrency or modeling weather patterns.
GPU时钟速度refers to the speed of the GPU. Generally speaking, higher speeds mean that the card performs tasks faster and produces a higher framerate when gaming. But like with CPUs, the clock speed is relative to each family of GPUs, so you can’t compare the clock speed of this GPU and assume it will get things done faster or slower than a GPU from NVIDIA with a different clock speed.
为了更好地理解GPU的性能和定性ties, you should check all of its specs, and there are a lot of them.
但是，如果您想对一个GPU的性能进行非常粗略的估计，则可以将流处理器数量乘以时钟速度。因此，例如，如果我们乘以270x的流处理器和时钟速度，我们将获得（1,280 x 1050）13亿。与290相比，在（2560 x 947）24亿中，我们可以肯定地假设290X比270X强大，即使270X的时钟速度更高。
因此，更高的时钟速度和更高数量的流处理器都是好东西，但是您无法查看任何单个规范来评估图形卡的性能。
通常，确定正确的视频卡的最佳和最简单方法是咨询现实世界的游戏基准。基准测量基于每秒帧或FPS，这是系统每秒呈现的游戏图像数量。较高的帧速率更好，当PC游戏时，60 fps是一个很好的框架，尽管节奏较慢的游戏可以舒适地降低到20 fps左右，而快节奏的游戏可以从比60 fps更高的帧率中受益。
To demonstrate how you can compare graphics cards through gaming benchmarks, let’s look at some benchmarks fromTechSpot对于巫师3，目前非常苛刻的游戏。
Here are the framerates at 1080p on Ultra quality. We can see the NVIDIA GTX 980 averages 56 FPS, while our AMD R9 290 averages 36. The 270X can only squeak out 14 FPS, which is essentially unplayable.
上升到1440p分辨率，帧率下降到GTX 980上的40 fps。对于290，我们看到下降到28，但仍可以播放，但远离理想的60多个fps。同时，270倍处于10 fps的完整幻灯片模式。
对于4K基准测试，我们将切换到另一个来源GamersNexus，因为他们测试了功能更强大的设置。
4K is a demanding resolution for The Witcher 3. Two GTX 980s averages 42 FPS at 4K resolution. Even the GTX Titan X, with its 12 gigabytes of VRAM, can only manage 36 FPS at 4K, while a single GTX 980 gets 26.
这使我们想起了我们应该提到的其他内容：多GPU设置。
In those 4K Witcher benchmarks, the best performance came from two GTX 980s which were operating in the same system. Assuming you have a compatible motherboard and power supply, a PC can have as many as 4 graphics cards working together to split up the graphical workload.
两个GPU的速度几乎是单个GPU的两倍。但是，添加第三个GPU，通常只会给您两个优势，而四个GPU很少比3更好。
这是战场4在1440p和4k上的表演的例子pcper.com）。您会注意到，四个GTX 980的表现实际上比三个表现差，因为添加第四张卡的复杂性超过了其提供的额外马力。
多个GPU的这种连接的名称不同于您使用的品牌。对于Nvidia卡，它叫SLI。有了AMD卡，它被称为Crossfire。
挑选出图形卡时，还有一些实际的考虑因素：电源，热量和噪音。
通常，您的图形卡是计算机中最多的耗电组件。像这290这样的单个GPU可以轻松从电源中取300瓦。添加多个GPU可以迅速增加功耗，这是需要进行电源升级的最快方法。
与计算机中的所有其他组件一样，图形卡浪费了约90％用作热量的功率，这意味着当您升级到大型图形卡或构建多卡设置时，良好的气流很重要。在选择构建案例时请记住这一点。
And when they’re under a high performance load, the fans on graphics cards can quickly become the noisiest thing in your computer. If you would like to keep your computer quiet, you’ll want to compare noise levels of different cards. Noise is a tricky thing to compare, because it’s difficult to measure consistently. You’ll have to find third party benchmarks to get useful noise measurements, and they won’t be directly comparable with noise benchmarks from different people.
以下是硬件.info的比较，显示了不同GTX 970和980s的负载噪声水平。较低的数字意味着较少的嘈杂。经验法则是，10分贝的差异听起来大约是大约两倍，因此最大的GTX 970超过大声两倍as the quietest GTX 970.
In conclusion, if you’re shopping for a new graphics card, we highly recommend familiarizing yourself with each card’s specs, comparing benchmarks, and checking out recommendations from reliable sources.
就像我提到的那样，NVIDIA和AMD每年或两年都会发布新一代的图形卡，因此最好确保您的建议是最新的。
In conclusion, if you’re shopping for a new graphics card, we highly recommend familiarizing yourself with each card’s specs, comparing benchmarks, and checking out recommendations from reliable sources.
每张图形卡中的GPU芯片是由NVIDIA或AMD制造的，但是该卡本身是由另一家公司（例如EVGA）制造的华硕或千兆字节。
这些制造商之间的主要区别将是客户服务，保修，和噪音水平和散热器的质量。
Helpful links:
- beplay软件逻辑增量PC建筑指南：Our expert PC build recommendations
- Anandtech GPU基准：轻松比较最新的图形卡
- GamersNexus：Reliable GPU benchmarks for games
- Videocardz.com：市场上任何图形卡的快速，简单规格
- game-debate.com：PC游戏的基准和性能信息
Graphics cards featured or mentioned：