HELP - S27a950d - looks awful @ 120hz

adambean

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Hey all,

Just hooked up my s27a950d. On HDMI, I was only able to achieve 60hz (is that normal?). After switching to DVI, I was able to get 120hz, but everything goes to complete crap, can barely see the screen. I then look at the menu on the screen it actually shows the picture went to 137.0kHz / 120HzPN / 960x1080. Not sure if this accurate as when I go to a lower resolution, the monitor menu still shows 1920x1080. Still though, that resolution would explain the awful picture I'm looking at.

I've updated my AMD drivers (12.4) for my Radeon 5800. I've downloaded and installed the drivers from Samsung (SMS27A950) to no avail.

I called Samsung and they were of no help at all.

Please help before I return.

Thanks!
 
Limiting to 60 Hz at 1920x1080 is normal over HDMI. Even though it's capable of 4096×2160p24 with 36 bits per pixel, which is enough bandwidth to run 1920x1080 at 153.6 Hz with 24 bits per pixel, the HDMI 1.4a specification doesn't require 120 Hz support.

From http://www.electronichouse.com/article/hdmi_1.4a_spec_addresses_broadcast_3d :

It lists the mandatory formats now as:

For movies - Frame packing, 1080p@23.98/24Hz
For game content - Frame packing, 720p@50 or 59.94/60Hz
For broadcast content - Side-by-side horizontal, 1080i@50 or 59.94/60Hz; Top-and-bottom, 720p@50 or 59.94/60Hz and 1080p@23.97/24Hz

As far as the issues over the DVI connection, the 960x1080 makes me wonder if the driver somewhere thinks you've got column-interleaved 3d. However, if you have a digital camera and can take a photo of the screen, and add it here, that might help me or someone else here figure out the problem.
 
The only thing I can tell for sure from that picture is that it shows you as having a "Generic PnP monitor", so you might not be able to get 120 Hz to work properly without that Samsung driver. A close-up of some of that text so I can tell what it's actually doing with the pixels might provide more information.

I skimmed the online manual for this model, and one other thing I can think of is you might check if the monitor has 3d mode set to "side-by-side", in which case you should change it to "frame sequential" or "off".
 
Wait, if the Generic PnP monitor is a second screen, why were you setting that one to 120 Hz in the photo? If you've got both DVI and HDMI connected from your computer to the samsung at the same time, so that Windows shows it as two separate monitors, that could be the problem right there.
 
You posted your follow-up while I was composing my reply, but from that image I can't tell how much of the poor readability is the fault of the monitor and how much is the fault of the camera (could be low-res camera and/or bad settings). Could you provide a close-up image that shows the sub-pixels for some text while it's set to 120 Hz (like TFTCentral shows for interpolation quality under the "General and Office Applications" sections of their reviews)?
 

adambean

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It's about the best picture I can take with my phone. Trust me, it's insanely bad ... it's non viewable. You can't make out what the text is, blurry lines, etc. It's without a doubt unusable in this setting. The only words of wisdom that Samsung could give me was "it's your video card drivers", which I find highly unlikely.

So this makes me wonder, what could it be? Video card, monitor, cable, drivers? I ordered a display port cable; however I'm tempted to just return it and maybe jump to the DELL instead.

I'm at a loss and rather bummed out about this.
 

adambean

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Well, you seem to know a thing or two about monitors ... I'm having a really hard time with the whole TN vs. IPS vs. 120hz for gaming. I'm not a hardcore gamer on PC these days ... I'd like to get back into shooters at some point; however right now, it's all for Diablo 3 and work. With that said, I'm in love with this 27' monitor (old monitor was a 23' LG). I'm not really debating jumping to the DELL U3011; however ... will an ATI Radeon 5870 be able to adequately support a 2560x1440 resolution?

Thanks
 

adambean

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Also, any suggestions on any other sites that I can post on for help with this Samsung 120hz issue? The more I continue to read, the more I'm at a loss of what to get If I do return this. I keep reading people love the DELL 27/30; however it also seems like more people are stating that 120hz is the superior choice for gaming ... but ... that comes with a caveat, of being able to achieve 120fps+, which I know I can't pull that with my current card, and I doubt I'm going to make that investment anytime soon.
 
Well, you could try hardforum, but it seems overwhelming to me - there's already a thread about the s27a950d that has 585 replies.

For Diablo 3, a 5870 should be able to handle 2560x1440. I would guess the performance would be in the neighborhood of the 6770 and 6850 that were tested in the recent article about Diablo 3 performance.
 

spellbinder2050

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This might be kind of late, but Samsung support told me that the S27A950D can only do 120hz via display port. Maybe that's why you're having some problems with it via DVI (Assuming that you're using Dual-link DVI, the only way 120hz would be possible using DVI, to my knowledge). If your GPU has it, try hooking up your monitor via the display port.

I'm actually in the process of figuring out whether that monitor can do 120hz via dual-link DVI, and I ran into this thread. :/
 

smc100

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I found this link while trying to figure this same issue with my own monitor.

I found the reason was I had the wrong dvi cable plugged in. I used my old dvi cable from my old monitor and did not know there are different types of dvi cables. What you need is a DVI-D Dual Link, the single link has two sets of nine pins, and a solitary flat blade while the dual link has three rows of eight pins and a solitary flat blade.

Single link cables use one TMDS 165Mhz transmitter, while dual links use two. The dual link DVI pins effectively double the power of transmission and provide an increase of speed and signal quality.