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Does Your LCD Play Catch-Up To Your Mouse?
Dishes of Ryan writes "I fell in love with the idea of an LCD monitor, so I ended up buying a nice, shiny Dell 2001FP. However, nowhere, and I mean *nowhere* did I read about LCDs having an input lag on them. For instance, if I scoot the mouse across the screen, there is a noticeable delay between when I move the mouse and when the cursor moves. To prove it to people, made a video showing exactly what I mean. You can almost forget being king of the hill on twitch FPS games like Unreal Tournament. Are there any other Slashdotters out there that are as annoyed as I am? What did you do?"
No offense, but you need to get another monitor. I notice no "lag" between my iBook and CRTs, nor do I notice any lag on my new 17" KDS for my desktop. Having developed a few video games and GUIs, I have a fairly well trained eye. I can see the problem in the video, but I see no such problem on my systems.
Conclusion? Dell buys parts from the lowest bidder. Ergo, they are the lowest quality. Therefore, you need a better monitor.
Sorry.
Javascript + Nintendo DSi = DSiCade
When I bought my LCD monitor I found all kinds of information in user reviews online. Check out New Egg, Amazon, etc. for all kings of discussion of this exact issue.
I've built countless systems with various high and low end LCD screens with no such lag. The worst screen I've encountered had the typical old-generation ghosting, but I've never seen input lag.
It may not be your LCD that's the problem. If you're using an IR or RF wireless mouse, there's a good chance the lag is coming from that.
The theory of relativity doesn't work right in Arkansas.
I've had zero problems on both of my laptops and every LCD I've ever used. Something's screwy with your hardware. It's rather sad that Slashdot posted this as a front pager...
That sounds much more like an issue with your computer than with your monitor. Does it do this with a CRT running the same resolution and refresh rate? I would bet so. LCDs have slower image response time (pixel rise/fall) than CRTs, but there is no significant delay between the time a signal reaches the monitor and the time it is displayed. In fact, implementing such a delay would be quite a challenge -- the information would have to be stored somewhere between the time it is sent to the monitor and the time it is displayed. This would require significant memory in the monitor to buffer several frames of video. Monitors don't do this.
I am a geek attorney, but not your geek attorney unless you've already retained me. This is not legal advice.
I wonder if it's the display that's lagging, or the video drivers? The last time I recall seeing an LCD display "lag" was back before the days of TFT screens
This seems to be a much more sensible explanation for the apparent lag. Even early TFT displays suffer from comparitively slow screen update intervals.
How the heck did this question make it past the editorial filter anyway? The idea that LCD displays are susceptible to some kind of input device lag specifically (as opposed to any other kind of state change that affects redraw) is preposterous.
Easy. Slashdot editors are idiots who don't care a wit for the content on the site. I mean really, this site could have so much potential, but it's really been squandered by the creators. Average people who don't want to cede control to people who could actualy do a good job.
/rant.
autopr0n is like, down and stuff.
Since when was /. an online PC troubleshooting forum? Any doofus knows LCD screen don't suffer from "lag" -- why doesn't he call Dell or ask on a newsgroup, not take out an article on the front page of Slashdot???
I have never seen lag attributable to a USB mouse.
In face, USB mice typically lag LESS than PS/2 mice because they update their position far more often.
The option in games isn't "REDUCE MOUSE LAG", it's "SMOOTH MOUSE", which is specifically designed around the problem of mice with low update rates (namely PS/2 mice, and in some cases REALLY crappy USB mice can have a slower update rate than a PS/2 mouse but it's RARE.)
retrorocket.o not found, launch anyway?
Does this effect only happen upon mouse movement, or do you detect the same problem while playing a video?
Did you try setting your monitor resolution to 800X600 or decreasing your colors to 16-bit?
Did you try resizing the window with your keyboard (e.g. in Windows using ALT+Space to activate the System menu)?
Did you try seeing what happens with a different OS? (e.g Knoppix)
Did you try changing your mouse drivers?
There are two kinds of people: 1) those who start arrays with one and 1) those who start them with zero.
At my dad's office we have a computer powered by a Parhelia hooked up to two UltraSharp 2001FPs (both through DVI...haven't tried it with analog cause whats the point) and I have never seen anything like this. They're just as good as a CRT (for CAD anyway) and the screens are gorgeous. My guess is USAR ERRAR
Now you've got me curious... No offense to the submitter, but this is obviously an isolated problem. Asking the average wage slave techie down at Best Buy could have confirmed this. Infact, nearly everybody on Slashdot has confirmed it to one degree or another. Soooo... Why is this frontpage news again? Will Slashdot start answering my unique one-shot hard drive problems now too? Hi, my name is Ed and my HDD is making an odd 'kerchunk' sound when it starts up. Have any other Slashdot users noticed this with their HDDs????? Why not? Let's convert the front page to miscellaneous hardware bug reports... Or not?
I'd submit to you that this question should have been handed off to any number of the flatscreen FAQ sites out there, especially given how unique the problem is. We're not exactly talking about ipod batteries here.
You need a FREE iPod Nano
My guess is that there is something wrong with the video drivers, or the mouse drivers, or some other part of his computer that's causing these problems.
If I remember the specs I saw when I was shopping for an LCD monitor about 18 months ago, LCD update rates are characterized in tens of milliseconds. The ones I was considering were in the 20 to 28 ms range. That's between one and two screen refreshes at 60 Hz. That's fast enough not to be noticeable.
If the monitor were causing the mouse to have a noticable lag, then everything else would appear to lag too. The guy needs to do some other tests - if he brings up a window and types, do the characters appear to be delayed too?
I'm with you - I think it's his mouse driver or some sort of strange interaction between the mouse driver and something he installed with the new drivers.
When *nobody* on *all* of Google has my problem, my reaction is that I'm doing something very wrong. I wonder why slashdot even publishes this question. I wonder why I'm even responding. I have a Dell 2001FP and have *never* had this "cursor lag" problem. I suggest its your video card, or driver, or maybe your machine has been taken over for use as a zombie. The 2001FP has about 4 different inputs, does the same problem exist on the analog as well as the DVI ports?
A) You can't "take out" an article on the front page of SlashDot; a moderator has to greenlight it.
B) What the hell is is to you anyway? Skip the damned article if you're not interested.
I have owned several Dell displays and have had no problems. I HAVE had lot of problems with "mice" over the years. In fact I had to replace my first generation Intellimouse optical wireless as it just did not work well with my new system. I would put the blame on the mouse, more than the LCD screen. It's amazing that this obviously minor problem has gotten so much attention: I.E. try another mouse before filming yourself and complaining to the entire internet community. Heck, I was having problems all around till I unplugged my bluetooth adapter.
"Jeremy, you need to get to an internet cafe and cut and paste some appropriate sentiments about me from the world wide
Moderators, say goodbye to your moderation priviledges.
(not kidding.)
She was replying to the parents, not the article, don't go refuting her perfectly intelligent post.
The definition of main is invalid in C99, but the reason it is accepted by compilers is that it is valid K&R C (which was amazingly lenient about function definitions; originally it didn't even check the types of function parameters, or convert them if they were wrong!). In fact, the old C89 standard included a lot of compatibility with K&R so it may be valid C89 as well (I can't find a copy of the C89 standard to check; stupid standards organizations). In K&R C function return values default to int if not specified, and parameters default to int too. Calling printf without a prototype I'm not so sure about; however it works on every C compiler I've tried. It appears that printf is built in to most compilers.
main(c,r){for(r=32;r;) printf(++c>31?c=!r--,"\n":c<r?" ":~c&r?" `":" #");}
I submit articles about the chips in "missile defense" systems being faulty, and they're shelved. Someone incorrectly configures their cheap monitor and it makes front page? WTF?
Here's the amazing answer: If it sucks, take it back.
Shit.
People, you are being misled! Those 20-28ms is only the delay! After that time it takes another 50ms (less on newer models with active matrix) for pixel to actually change colour. All people who are saying LCDs perform as well as CRT aren't comparing them side-by-side. Most of you got shiny new LCD with shiny new computer... and it feels better because you have better computer, not becuse of LCD. Especially in gaming CRTs are much faster than LCDs. If you don't notice that you are blind. Or you are comparing it to CRT at 60Hz which is overkill for eyes and brain. Modern CRTs have no problem operating at 120Hz - use that! As for "i don't see skipping mouse pointer on my lcd".. you probably use default windows drivers for mouse, which caps your mouse refresh to 40Hz.. of course you don't notice anything. Download "ps2rate" utility to measure your mouse rate. Even usb mice with default drivers default to 40Hz.
I'd be willing to bet that it is the monitor. Maybe it's just a fluke, or maybe it's just a bad model. Dell isn't exactly known for excellent quality, regardless of who makes the underlying components. I've found especially with the rush to the LCD market that many displays do not perform as specified, especially those that are coupled with a TV tuner. It is basically shocking how shoddy some of this stuff is, and it's even more shocking that we are paying for it and not complaining. Of course, you can also get lucky like I did and get a brand-new $300 17" LCD that performs on par with Apple's 17". Unfortunately, that deal has come and gone.
I am feeling fat and sassy
First of all, thank you, everybody, for taking a look at this. I received a characteristically Slashdotty wealth of "you're an idiot" replies, and a good number of "I didn't read the full article and/or watch the video so I'm jumping to conclusions" replies as well. =) Those of you that read the article and offered your genuine insight, thank you.
It's all fine, though. I'd like to answer a few randomly culled questions here, and also summarize what I've found based on all the feedback so other potential LCD owners can get a better feel for what they're up against.
The overall summary, which you may or may not agree with is: Most LCDs are laggier than CRTs (I'd be jumped in an alley if I went as far as to say *all* LCDs are, but I try to avoid sweeping generalizations). Do your own tests, and come to your own conclusions. If you're a gamer, be careful. And lastly, my Dell 2001FP may in fact be one of the laggiest LCDs in existence, *or* I just received a defective unit.
Thanks again, everybody, for the replies. I hope this helps some people. I know that I at least saw one person in the comments that learned something new, although it was, in fact, for something unrelated to the immediate post. =)