Dual 22" LCD monitor slow down the desktop performance?

[T. T.]

Hi there, how are you doing?

We just bought two 22" widescreen LCD monitors to replace our two old
19" CRT monitors. By the way I can't remember what was the resolutions
that I had for running the two dual 19" CRT monitors. Here is my
hardware configuration:

CPU: AMD athlon XP 3500+ CPU (single core)
Memory: 1GB
Graphic Card: ATI Radeon x850 (AGP) 256MB
Currently running these two LCD monitors at 1680 x 1050 native
resolution

After I set it up, I noticed that now even when I was dragging my
mouse over the desktop, the mouse sometimes would move slower (I have
a optical mouse), and the overall performance of the Windows XP
desktop seems to be slower too (e.g. opening up multiple Windows,
etc.). Here are my questions:

1. Is this performance issue that I'm encountering related to the fact
that I'm running two big screen LCD monitor at 1680x1050 (each), that
the AGP video card needs more "juice" to output so many pixels at the
same time? The reason that I chose to run this kind of set up was that
I am a fan of running dual monitors (for programming and flight
simulation reasons). Would I be better off if I just run it on ONE 22"
LCD monitor or even buy a 26" LCD monitor like this one (http://
www.costco.com/Browse/Product.aspx?Prodid=11236988&search=28%22%20LCD&Mo=0&cm_re=1_en-_-Top_Left_Nav-_-Top_search&lang=en-US&Nr=P_CatalogName:BC&Sp=S&N=0&whse=BC&Dx=mode+matchallpartial&Ntk=Text_Search&Dr=P_CatalogName:BC&Ne=4000000&D=28%22%20LCD&Ntt=28%22%20LCD&No=0&Ntx=mode+matchallpartial&Nty=1&topnav=&s=1,
which is running 1920 x 1200 WUXGA ?) Should I consider to upgrade my
video card, or even my entire system? Would dual core CPU help with
this kind of performance issue (or it is purely "graphics card"
issue)?

2. Is there any way I could "tune" my current setting so that at least
the "Windows XP" desktop could speed up a little bit (or run more
smoothly), I have already set up the Windows XP (My Computer -> System
Properties -> Performance -> Adjust for best performance), but it
didn't help much..

Please help! Thanks!

 

[Mike Ruskai]

We just bought two 22" widescreen LCD monitors to replace our two old
19" CRT monitors. By the way I can't remember what was the resolutions [snip]
After I set it up, I noticed that now even when I was dragging my
mouse over the desktop, the mouse sometimes would move slower (I have
a optical mouse), and the overall performance of the Windows XP
desktop seems to be slower too (e.g. opening up multiple Windows,
etc.). Here are my questions:

[snip]

It's conceivable that you're running higher resolutions that slow
things down, but I wouldn't peg it as likely.

What you describe sounds suspiciously like "input lag", which is
actually output lag. Some LCD panels buffer several frames of output
to do comparitive image processing on them (to remove artifacts
peculiar to LCD displays), which has the effect of delaying screen
output by 20-60ms.

So when you drag a window, it'll feel sluggish.

If you provide the make and model of the displays you have, I can look
up the panel type and see if it's one that suffers from such lag
(typically PVA panels are the sufferers).

If that is the case, your only recourse is to return the monitors and
get ones that don't use laggy panel types. Anything with an IPS panel
is good. A plain TN panel (*not* Overdrive TN, which has the lag
problem) is also good for this particular problem, but suffers with
respect to color reproduction and viewing angle (but are much less
expensive than IPS panels).

 

[T. T.]

Hi Mike thanks for your reply. I just noticed that when I do the
"Windows Update" it prompted me to download a nvidia driver and after
I did that, now the problem is gone. I guess that in this case the
latest nvidia display driver had something wrong with it, while the
"certified" windows display nvidia driver fixed this issue. just a
quick fyi

 

[Eric Gisin]

What you describe sounds suspiciously like "input lag", which is
actually output lag. Some LCD panels buffer several frames of output
to do comparitive image processing on them (to remove artifacts
peculiar to LCD displays), which has the effect of delaying screen
output by 20-60ms.

Bullshit. No LCD stores more than one frame.

 

[Mike Ruskai]

Bullshit. No LCD stores more than one frame.

So S-PVA, S-MVA, and Overdrive-TN panels just sit there delaying a
single frame for 20-60ms? Is that the story you're trying to sell?

 

[Eric Gisin]

So S-PVA, S-MVA, and Overdrive-TN panels just sit there delaying a
single frame for 20-60ms? Is that the story you're trying to sell?
--

I thought there might be one RAM frame buffer,
but looking TFT-LCD in wikipedia there is none at all.
The article on Input lag doesn't mention buffering at all.
So your claim is even more outrageous. Crackpot.

 

[Mike Ruskai]

I thought there might be one RAM frame buffer,
but looking TFT-LCD in wikipedia there is none at all.
The article on Input lag doesn't mention buffering at all.
So your claim is even more outrageous. Crackpot.

You're using Wikipedia as an authoritative source of information, and
I'm the crackpot?

You didn't answer the question. Do you think the displays have such
pitifully slow ASICs that they're simply delaying a single frame by
20-60ms?

Or are you just a crank who wants to be contrary?

 

[Bob Myers]

\>>>Bullshit. No LCD stores more than one frame.

I thought there might be one RAM frame buffer,
but looking TFT-LCD in wikipedia there is none at all.
The article on Input lag doesn't mention buffering at all.
So your claim is even more outrageous. Crackpot.

Actually, not so "crackpot" at all. It's just that the
storage (for the most part) isn't happening within the panel
itself. (There COULD be up to a frame's worth, there,
depending on just what and how the panel electronics,
meaning the timing controller in this case, do their things.)
Don't forget that the "front end" electronics - the scaler/controller
IC and such - is where a good deal of the monitor's features
are implemented. Having 20-60 msec of latency, overall
between the video input and the display of the image on the
screen is by no means unheard of.

Bob M.