22 inch CRT, got some questions

Ante P

Veteran
I just got a brand new iiyama 22 inch CRT monitor. :)

I'm currently having some problems though.

First of all I have installed the monitor drivers yet not even the recommended resolution is available. I checked the inf and sure enough it's basically empty apart from configuring max res)

Now problem 2: the recommended res is 1800x1440 @ 94 Hz with +/+ polarity. So first of all that isn't even available.
So I added it myself, and it works ok at 85 Hz. But if I go beyond 90 Hz it starts cropping the bordsers of the screen (not configurable).

Another problem: all resolutions are set to +/- polarity instead of +/+ even though the inf says +/+ and is installed properly. I'm guessing Forceware doesn't behave properly so I tried fooling around with which timings it should use but that didn't work either.

And now for the most annoying problem:
Whenever I go over 1600x1200 @ 100 Hz the image starts to get fuzzy.
Which is pretty bad since 1600x1200 is lower than the recommended resolution.
1800x1440 looks pretty ok, but 2048x1536 @ 85 Hz which is the max resolution is fuzzy AND I get ghosting.

The cable I use came with the monitor and looks high quality. It's very short, it's thick and very properly shielded plus has gold plated connectors of course.

Now to what I think the cause might be:
I have a 6800 Ultra with only DVI outputs so I have to use a DVI-VGA adapter.

Does anyone have more in depth knowledge on how that might affect high res output?

The adapter itself looks pretty high q and was fairly expensive (about 20 bucks). I haven'ät really found any high end adapters so I don't think I can shop my way to a better image quality per se.

The real kicker is that other people using 2048x1536 on CRTs on 6800 with DVI-VGA get a very crisp image.

As a sort of last resort I tried eliminating the extra connection by buying a high q DVI-A to VGA cable (ie DVI-VGA adapter "within" the cable) but that just turned my image all purple for some reason and besides it still didn't look sharp at high res.

So, any ideas? :)

Sorry for the ultra long post.
 
And btw: the answer is not:
"The monitor can't handle it" - I know it can, I tested it before I bought it.
"Anything above 1600x1200 is silly" - No it's not, if I could do with low res I wouldn't have bought this monitor in the first place. ;)

Oh yeah. The screen is a perfect 4:3 ratio (40 times 30 centimeters to be exact). yet the recommended resolution is 5:4 ratio. Any ideas why the manufacturer would recommend that?
 
Well the fuzziness at high resolutions could be a weak ramdac, have you tried a different video card?
 
AlphaWolf said:
Well the fuzziness at high resolutions could be a weak ramdac, have you tried a different video card?

Not yet no, it has dual 400 Mhz RAMDACs and at 1800x1440@85 Hz I'm just a bit above 300 Mhz so it should have some "power" to spare.

But as I said others with 6800U don't seem to have this problem.

Or do you mean that perhaps the ramdac quality can vary between different boards even though they're using the same type of components?
 
is your card a Leadtech? or a ASUS?


" Or do you mean that perhaps the ramdac quality can vary between different boards even though they're using the same type of components"

very much.
 
karlotta said:
is your card a Leadtech? or a ASUS?


" Or do you mean that perhaps the ramdac quality can vary between different boards even though they're using the same type of components"

very much.

It's a reference board (pretty late revision), according to what I've heard it's supposed to have really top notch components.

Bad news on varying ramdac quality then I guess. :/
 
Could it be a problem with DVI to analogue conversion?

That could make sense as seem to remember DVI signal is not going to provide good image beyond 1600x1200 as the standard runs out of bandwidth something or other like that?

Try a card with good analogue output first like some old ATI or Matrox card...
 
lol, now check this out

I was using the power cable that was connected to my old monitor at first.
But in my desperation I changed to the one that came with the monitor (a bit more sturdy looking)

now 1800x1440 is sharp as can be (2048x1536 still a bit fuzzy but less noticable)
but now instead ghosting is apparent in 1800x1440 and even worse in 2048x1536

good thing my salary this month is massive
I'm gonna go out and buy the best quality power and monitor cables + dvi adapter that I can find
 
The latter might be the monitor bedding in. It can take time to get used to it's new position in the earth's magnetic field.

You might not have seen the ghosting before because of the blurry image quality :)

Ghosting is invariably cable problems. In theory you can calculate where the problem is on the cable using the distance of the ghost, the dot clock rate, and the speed of light down the cable (around 1/3c in most metals if I remember right, that's from a really long time ago though). That kind of calculation was essential in the coax ethernet cable days...
 
Ante P said:
good thing my salary this month is massive
I'm gonna go out and buy the best quality power and monitor cables + dvi adapter that I can find

I can testify to getting good BNC cables instead of the VGA standard ones really make a differnce, - have a Philips 202p4 and is using it in 2048x1536 @80Hz.

Hope it works out for you.

Cheers
Gubbi
 
Gubbi said:
Ante P said:
good thing my salary this month is massive
I'm gonna go out and buy the best quality power and monitor cables + dvi adapter that I can find

I can testify to getting good BNC cables instead of the VGA standard ones really make a differnce, - have a Philips 202p4 and is using it in 2048x1536 @80Hz.

Hope it works out for you.

Cheers
Gubbi

I don't have BNC input though so that's a no go.
 
BTW are you also using a 6800?
Input from other dual DVI 6800 users with standard CRT monitors at res above 1600x1200 would be very much appriciated.

If I can't solve my problems I might as well try to trade this board for a X800 XT PE. Or perhaps I'll wait for a X800 XT PE 512 MB.
 
Ante P said:
Gubbi said:
Ante P said:
good thing my salary this month is massive
I'm gonna go out and buy the best quality power and monitor cables + dvi adapter that I can find

I can testify to getting good BNC cables instead of the VGA standard ones really make a differnce, - have a Philips 202p4 and is using it in 2048x1536 @80Hz.

Hope it works out for you.

Cheers
Gubbi

I don't have BNC input though so that's a no go.

That's really suprising for a top end monitor... I'm not sure exactly what you can do in that case other than running at a lower resolution. Even at 1600x1200 BNC cables can make quite a difference for image quality.

Nite_Hawk
 
Nite_Hawk said:
That's really suprising for a top end monitor... I'm not sure exactly what you can do in that case other than running at a lower resolution. Even at 1600x1200 BNC cables can make quite a difference for image quality.

Nite_Hawk

Many of the newer high end 22" CRTs don't seem to have BNC, dunno why.

I still imagine that the DVI has something to do with this all so I'm going to try a X800 XT to see if the VGA output is better suited.
 
From what I know a fuzzy image can be the fault of a cable with a ferrite core (the bulky thing at one or both ends of a cable that filters high frequencies coming from noise as well as from the image itself!).

You should get ghosting with a bad shielded cable (thinner than a properly shielded cable) as well as with increasing length of the cable.

So buy a properly (double) shielded VGA cable without a ferrite core and it has to be short (~ max 2 metres for the resolution you want).
I paid 5 euros for that.

You need BNC if you need longer cables.

I tried switching to highest resolution (1600x1200) and I get no difference in image quality when using a DVI-VGA adapter.


edit: There are "highend" cables with 3 coaxial conductors for the colour signal. I don't know wether my cable has that (if every descent cable has that) link.
 
Ante P said:
And btw: the answer is not:
"The monitor can't handle it" - I know it can, I tested it before I bought it.
"Anything above 1600x1200 is silly" - No it's not, if I could do with low res I wouldn't have bought this monitor in the first place. ;)

Oh yeah. The screen is a perfect 4:3 ratio (40 times 30 centimeters to be exact). yet the recommended resolution is 5:4 ratio. Any ideas why the manufacturer would recommend that?


Are you sure that the particular monitor you have can handle it?

monitor quality varies, some have better focus than others, I've had 6 different iiyama VM pro 454s from one that blurred at 1600x1200 @ 85Hz to two that were razor sharp even at it's max of 2048x1536 @ 83Hz

Download a monitor testing app (google for "nokia monitor test" turns up a nice one), set your refresh rate to 1600x1200 @ 100Hz or 2048x1536 @ 85Hz and then in the testing app select the geometry mode and then inspect the horizontal lines. If the lines get thicker in places then the monitor has poor focus. For the ghosting put the OSD up, if that gives streaking or after images of itself than the monitor is also at fault for the ghosting. For either it's time to phone up iiyama and get them to bring you a replacement :)
 
The OSD is perfectly sharp at 2048x1536.

I'll try the nokia monitor test later on, thanks for the tips!
 
Aren't the RAMDACS intergrated onto the actual GPU? So I doubt the quality of those can be different, maybe the filters or something can vary in quality from different cards, but aren't most cards reference boards?
 
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