7850 horizontal white lines using VGA (d-sub)?

[EvilAngel]

Hi everyone,

I recently got a MSI HD 7850 but I'm having one issue with it. My main monitor only has a single VGA input and no other inputs of any kind and I'm getting some pretty noticeable horizontal flickering white lines (like having a very low refresh rate on a CTR monitor).

I have tried 3 DVI to VGA adapters, 2 Mini Dual Port to VGA adapters and 3 different VGA cables with pretty much the same results.

The card works great on my TV over HDMI and also works great on a old 17" Dell monitor over DVI.

There seems to be something wrong with the way the digital inputs are converted to VGA on this card(s?). I know it is a Videocard <--> Monitor issue because screenshots look great.

The same monitor works perfectly fine at 1920x1080 @ 60hz on:

- Same PC using integrated graphics (using the same DVI adapters)
- Same PC using a Sapphire 6870 (using the same DVI adapters)
- My laptop with a native VGA out port.

After googling around I don't know if this is an issue with my particular card or all/most HD7xxx.

Is anyone using any digital (HDMI/DP/DVI) to VGA adapter without issues on these cards? Any possible solutions aside from buying another monitor with DVI/HDMI/DP inputs?

Thanks!

 

[fixedmy7970]

I use a DVI to VGA adapter on my 7xxx cards. It works fine on the 7950, no flickering. But on my 7970, there is flickering but not horizontal white lines, just a really jittery screen that eventually goes away if I up the clocks.

since the dvi works find with the Dell monitor, maybe try another monitor. I doubt the adapter is the cause.

maybe try,
- amd beta drivers
- changing refresh rates in CCC, set to match desktop
- enable gpu scaling?

 

[EvilAngel]

Hi, tried everything you listed and still the same issue at all refresh rates and resolutions, same with the latest beta drivers, i even OCed the card to 1000mhz core 1250 memory and get the same.

Is it possible to use my i7 integrated video to output to the monitor while still using the video card for performance?

 

[fixedmy7970]

that is a good question, i don't think so though.

however, does this occur all the time or only while gaming?
if only during gaming, try capping fps at 60 or 75.

i did some googling for ya, try this,

1.Open Screen Resolution (from Control Panel or from the desktop)
2.Click on Detect
3.Click on the Display list and choose Available display output on: &#8230;
4.Click on the Multiple displays list and choose Try to connect anyway on: VGA
5.Click on Apply
6.Click on Multiple displays and choose Extend these displays
7.Click on Apply and after that confirm the changes

from what I've read, you might have to bite the bullet and get a new monitor with a dvi or hdmi. it seems the white lines are the result of noise from the dvi to vga adapter

 

[EvilAngel]

Thanks a lot for trying!

I did find a sort-of-solution using a software called Lucidlogix's Virtu MVP that is compatible with my Z77 motherboard.

It allows you to use the motherboard integrated video output and still use the video card performance while doing so, supposedly to save power and gain performance but it also fixes my problem.

The downside is that the software is not cheap, I just started using the 30 day trial and i will probably just buy another monitor at the end of the trial with DVI/DP or HDMI input and be done with this.

But i still don't understand whats wrong with this card and the digital to analog conversion since it works perfectly fine with everything else.

 

[Tamlin_WSGF]

The clock and phase settings on your monitor is probably off. Most VGA only monitors have an auto button on the screen which adjusts this automatically, while some have it in the screens menu.

If it doesn't have an auto setting and you need to do this manually, here's a good test picture:
http://www.lagom.nl/lcd-test/clock_phase.php