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A quick Google search reveals that the maximum resolution for VGA is 640x480. However, I'm currently using VGA at a resolution of 1366x768 and it's working fine.
How does this not malfunction?

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    bluecinetech.co.uk/vga-max-resolution the second link on google: "While the original VGA (VGA standard) had a maximum resolution of 640×480, nowadays the VGA cable is capable of 1080P and higher resolutions."
    – Gantendo
    Apr 18, 2022 at 4:56
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    no doubt. I've used VGA cables often since 1993, which is about the last time that 640*480 was really a PC resolution. even safe-mode has been 800*600 for decades, yet you can still find 1080p monitors with VGA ports that will work just fine. I'll admit I haven;t tried it with 4/8K, since those generally only have HDMI/DP ports, but who knows. Apr 18, 2022 at 6:08
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    "A quick Google search reveals that the maximum resolution for VGA is 640x480." - No, a quick Google search reveals one page that is wrong, followed by several that are correct. Don't believe just the first search result you get.
    – marcelm
    Apr 18, 2022 at 20:29
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    You are using what used to be called "Super VGA" or "SVGA". en.wikipedia.org/wiki/Super_VGA
    – Kaz
    Apr 20, 2022 at 22:24

2 Answers 2

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"VGA" has two meanings:

  • A specific graphics card, the IBM Video Graphics Array from 1987, which supported resolutions up to 640×480 (now known as the "VGA" resolution), and which also introduced a new video connector type that's now known as the "VGA" connector.

  • The 15-pin analog video connector introduced by the IBM VGA but later used for 35 years by probably every other graphics card in the world.

So when people talk about the 640×480 limit, they refer to what the IBM "VGA" chip could output. The physical connection, however, can handle much higher resolutions, although it depends on the cable quality and shielding (at some point the analog signal begins to deteriorate).


(And the IBM VGA controller technically could generate video signal in higher resolutions, but mainly in text mode – e.g. the "80×25 characters" mode would generate a 720×400 pixel output.

Wikipedia also talks about it being possible to tweak the graphics mode to go as high as 768×576 if you didn't mind headache-inducing low refresh rates, but I don't think any OS offered such resolutions by default.)

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    Its worth adding that VGA hlimplements EDID to facilitate negotiation of the resolution- see extron.com/article/uedid
    – davidgo
    Apr 18, 2022 at 6:22
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    VGA evolved into Super VGA (SVGA), which is a collection of different resolutions (and refresh rates). SVGA uses the same signalling as VGA
    – CSM
    Apr 18, 2022 at 13:56
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    Not that it would matter, but 35 years is an overstatement. Most if not all graphics cards sold in the last 5+ years lack a VGA connector. It's typically a bunch of DisplayPorts with the occasional HDMI or DVI.
    – TooTea
    Apr 18, 2022 at 19:27
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    @TooTea: Most video-card DVI ports still have the analog pins as well, right? So a passive DVI->VGA adapter can work. Some budget motherboards still have VGA ports, although it does seem to finally be losing popularity with gaming boards. It's about time; in the early days of LCD monitors, the cheap ones only had an analogue VGA input! (Since that was necessary given the ecosystem at the time, and a DVI input as well would cost more.) Apr 18, 2022 at 20:12
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    640*480 = 307200, 720*400 = 288000 so depending on what you count, 720x400 is not a higher resolution.
    – Arsenal
    Apr 20, 2022 at 11:29
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VGA is an older signalling standard where a pixel is transmitted on only three pins by using analog voltages.

Each of these voltages is represented as a voltage level between 0 volts (no intensity) and 0.7 volts (full intensity). So a pure black pixel will have the signal level of 0v,0v,0v on the three lines, while a pure white pixel will have an ideal signal level of 0.7v,0.7v,0.7v on the three lines and so on.

enter image description here

This means that VGA is capable of transmitting in any resolution at all, one pixel at a time. Cable quality and transmission speed count strongly for the quality and responsiveness of the display.

From Wikipedia VGA connector - Cable quality:

The same VGA cable can be used with a variety of supported VGA resolutions, ranging from 320×400px @70 Hz, or 320×480px @60 Hz (12.6 MHz of signal bandwidth) to 1280×1024px (SXGA) @85 Hz (160 MHz) and up to 2048×1536px (QXGA) @85 Hz (388 MHz).

There are no standards defining the quality required for each resolution, but higher-quality cables typically contain coaxial wiring and insulation that make them thicker.

See How Many Dots Has It Got for what is today still called VGA, but has evolved far beyond 640x480. The resolution champion today seems to be WHUXGA (Wide Hex Ultra Extended Graphics Array) with resolution of 7680x4800 (36,864,000 total pixels).

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    "any resolution at all" <-- well, subject to band limiting characteristics of the physical conductors and connector, which becomes a limiting factor at some point. Apr 18, 2022 at 17:13
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    @R..GitHubSTOPHELPINGICE: Of course - as mentioned. In general there is no limiting connection between VGA and resolution, except the performance of the used components when transmitting one pixel at a time.
    – harrymc
    Apr 18, 2022 at 17:28
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    So the resolution could be infinite if you don't care about Frames per Day being your metric and a bit of monitor and graphics card hacking
    – Hobbamok
    Apr 20, 2022 at 10:56
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    @Hobbamok: "Infinite" in the same sense as 9800 baud once seemed to be the maximum that could be squeezed through a copper phone line, 10 MBit/sec for a ethernet cable, or 1 MB/sec for a USB cable. Then we jacked up the electronics at either end and the requirements for the cables and connectors, and were able to push things by several orders of magnitude. At some point it became easier / cheaper to create a new connector, and we switched, leaving behind some tech that still could have another order of magnitude squeezed out of it.
    – DevSolar
    Apr 20, 2022 at 12:14

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