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177

Based on what I've found in the source code: VBoxVGA This emulates a graphics adapter specific to VirtualBox, the same as in previous versions (<6.0.0). This is the default for images created for previous versions of VirtualBox (<6.0.0) and for Windows guests before Windows 7. It has some form of 3D passthrough, but – if I remember correctly – uses ...


59

You need a HDMI-to-VGA adapter. Your laptop is outputting an HDMI signal which has to be converted to VGA. Some connectors are physically different, but use identical signaling - in these cases a passive adapter is sufficient. Passive means there's no signal transformation necessary. It's just two different connectors wired together. For example, DVI-A is ...


49

You need to add a new panel to the second screen, and add a task manager to that. Right-click on the background of the second screen -> Add Panel -> Empty Panel. If you know how to move panels and add widgets to the panel, then move the panel to where you want it, add the tasks widgets, then set it to also only show widgets from the current screen. If ...


47

Let's look at the signals in a VGA connector: Pins 1, 2, 3: (R, G, B) 0 to 0.7V analog color signals to the monitor Pins 13, 14: (Hsync, Vsync) 0 to 5V TTL synchronization signals to the monitor Pin 9: 5V power to the monitor's I2C EEPROM Pins 12, 15: (SDA,SCL) 0 to 5V I2C clock and data to/from the monitor's EEPROM Pins 11, 12, 4, 15: (ID0,ID1,ID2,ID3) ID ...


44

VGA is the only analog signal from the above mentioned ones so it's already an explanation for difference. Using the adapter can further worsen your situation. some further reading: http://www.digitaltrends.com/computing/hdmi-vs-dvi-vs-displayport-vs-vga/


31

But they do tell you quite explicitly when you should prefer them: – VBoxSVGA: The default graphics controller for new VMs that use Linux or Windows 7 or later. This graphics controller improves performance and 3D support when compared to the legacy VBoxVGA option. Linux or Windows >7 improves performance and 3D support – VBoxVGA: Use this graphics ...


26

Many people get this the wrong way round. Signals go from > to You might think you're connecting your display to your computer, but you're not. You're connecting the computer to the display. This means your signal goes from the computer to the display - that's an HDMI to VGA connection. HDMI is a digital format, VGA is an analog format, so any connector ...


25

I had a similar issue with one of my dual monitors not showing up after resuming from sleep. I used the keyboard shortcut Ctrl+Shift+Win+B to restart the graphics driver and my main screen flickered off and then both screens turned on. There's some more information in this question.


24

VGA is analog. HDMI is digital. Meaning: the digital output of your computer is converted to the analog VGA signal. The analog VGA signal is converted back to a digital signal by your monitor. These conversions depend on the quality of the involved cable, connectors and especially the analog/digital converter components within your graphics card and the ...


18

Each and every VGA flat-panel display has an "Auto" button. It automatically adjusts the interpretation of the analog signal to achieve a (more or less) pixel-perfect mapping. Activate this function when the outer edges of the image displayed are clearly defined (nothing black) and you have text visible. Still, 1080p is in the upper regions of what's ...


16

Performance is one difference. Testing with glxgears, I get: VBoxVGA: 60fps +/- 2 (very low, but moving a window around is not smooth so it seems plausible) VMSVGA: 1570fps +/- 50 (after a reboot, I get 1300fps +/- 200?!) VBoxSVGA: 970fps +/- 30 (in this mode, Cinnamon warns me that the desktop environment's graphics are running on CPU) The guest additions ...


14

Basically, HDMI is digital and VGA is analogue. There are a few solutions: 1) Buy a docking station which provides access to 2x HDMI or 1x HDMI + 1x DVI. 2) Use an on-board DVI instead of the VGA. 3) Buy a HDMI -> VGA converter. The 1st VGA will no longer seem blurry in comparison with the HDMI.


11

Assuming brightness,contract and sharpness are the same in both cases, there could be 2 other reasons why text is sharper with DVI/HDMI: The first has already been stated, VGA is analog so will need to go through an analog to digital conversion inside the monitor, this will theoretically degrade image quality. Secondly, assuming you are using Windows there ...


10

The pixel clock adjusts how wide the input pixels are. VGA is an analog input, there are no clear-cut boundaries between pixels and the monitor must guess. If the clock setting gets misadjusted, your display gets blurry and that’s probably why it no longer causes interference. To adjust the clock and phase settings properly, view a pixel checkerboard on ...


10

As others have said, VGA is an analog signal but the pixels in a flat panel display are digital. The monitor has to know where in the VGA analog waveform to sample the signal to convert it to digital. The auto adjust feature on flat panel displays attempts to guess the best timing for that sampling. But if the timing isn't perfect, you will get a blurry ...


10

You are right: HDMI, DP and DVI-D use digital signals, while VGA uses analog signals. You'll need to buy adapters that convert those digital inputs to analog outputs (so yeah, no "passive" adapters). VGA degrades quality quickly with bad/long cables as well as with high resolution displays (it'll need to send analog signals, changing the output voltage at ...


9

Basic VGA cables are comprised of fifteen wires and support resolutions of 640x480 or less. If you use a cable like this on a modern computer with a higher resolution, it will probably display some kind of picture but with significant ghosting. High-resolution VGA cables (sometimes called SVGA, Coax VGA, premium VGA, etc.) are comprised of three coaxial ...


9

That's a passive adaptor. It converts a DVI-I into a analogue VGA port. More precisely, it breaks out the analogue portions of a DVI-I connector. It will not work in a proper DVI-D port (or an improper one with a DVI-I socket). To actually convert DVI-D (or any real digital out - displayport, hdmi ect) to VGA you need an active adaptor. If its a DVI-I ...


9

Are you connecting a monitor or a TV? Below are some methods that could perhaps solve the problem, singly or several together : Method 1 : Use a tool to force the resolution Here are some command line tools that can change the screen resolution : QRes, NirCmd, Display Changer. Method 2 : Registry updates Search the registry for DefaultSettings....


9

I'll go through your Q point by point. Do I need (hdmi to vga adapter) OR (vga to hdmi adapter)? My common sense would tell (vga to hdmi adapter), but I am not 100% sure. Well, the exact naming of the adapter will depend on the vendor, but most vendors put the video source (computer) before the "to", and the video target (monitor) behind it. So &...


8

As @Wyzard says, computers talk to monitors via DDC and this uses 4 pins on the vga. See the pinout on wikipedia. A working vga cable needs all the pins wired independently from each, and also from the cable shielding to the chassis, i.e the metal cover of the plugs and sockets. Only pins 4 and 11 can be missing or not cabled. Inside a monitor there is a ...


7

A little late to the game, but this one I know :) As of Driver version 353.30: Go to NVIDIA Control Panel -> Display -> Change Resolution Look for "Output color format" and change the setting from 'RGB' to 'YCbCr444' Update in response to fixer1234: The fix isn't so much magic as a little bit of troubleshooting logic. At first, I thought the monitor was ...


7

The others make some good points, but the main reason is an obvious clock and phase mismatch. The VGA is analog and is subject to interference and mismatch of the analog sending and receiving sides. Normally one would use a pattern like this: http://www.lagom.nl/lcd-test/clock_phase.php And adjust the clock and phase of the monitor to get the best match ...


7

Regarding Linux specifically, the usual reason I've heard is "we don't want it in the kernel". Especially when it comes to fonts and languages – no kernel developer wants to fall down the slope of adding support for TTF, antialiasing, RTL, animated emojis, eventually running all of freetype2 and ICU in kernel space. Rather, they put in the kernel what makes ...


7

As per the Wiki article on DVI: A passive DVI-to-VGA adapter. This adapter will not work with a DVI-D output. It requires a DVI-I or DVI-A output to get the analog signal to a VGA input (even if the adapter looks like a DVI-D). A more expensive active adapter (or converter) is required to connect DVI-D to VGA. As such you would need an active adapter in ...


6

The cited "specs" of your cable are only advertising words. It is usually difficult to get specifications (loss, shielding, capacity, ...) of a cheap cable. Some cables use a ferrite cylinder increase the inductivity of the cable. This helps to suppress high frequency noise. May be the "chirp" vanishes, if you use a ferrite. Check if both cables used a ...


6

This is going to be somewhat a dance of concepts, but: I think we can say VGA is hot swap-able for a few reasons: Windows, and in fact Linux and other operating systems have built in handlers to make hot swapping a monitor effortless, and painless without any rigamarole. As previously noted, when you plug in a monitor or change to a projector from a ...


6

Any VGA only monitor in this day and age is seriously obsolete - most older monitors would be at least DVI capable. Your video card reflects that and has no ports that can be "passively" converted into VGA. Looking at your ports, that's a purely DVI-D port. It won't work. More accurately, the adaptor won't fit, and the analogue pins don't exist. If you ...


6

If you look at the Wikipedia article for DVI, especially the pinout, you'll see that DVI also can carry analog signals (the variant called "DVI-A"). That's why DVI to VGA adapters work: They take the the analog signals from the DVI-A pins, and route them to the corresponding VGA pins. So if your graphics card doesn't support analog pins on the DVI connector ...


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