Aces High Bulletin Board

General Forums => Hardware and Software => Topic started by: Greebo on July 08, 2009, 05:53:19 PM

Title: LCD monitors and input lag
Post by: Greebo on July 08, 2009, 05:53:19 PM
My old Mitsubishi 20" CRT has developed the annoying habit of going to a black screen from time to time. It has a loose connection of some sort and a few good whacks will soon get the picture back. I've had the back off of it but can't trace the fault. As these sort of problems only get worse with time, it looks like I will soon be needing a new monitor. Today that means an LCD display so I've been doing some research on them. This is an excellent site BTW: http://www.tftcentral.co.uk (http://www.tftcentral.co.uk)

I need a monitor with good colour reproduction and the HP LP2475w is my current favourite. This monitor has some input lag issues however. Input lag is how long it takes for the image to get from the video card to appearing on the screen. On the HP it averages at 25ms worse than my CRT which is almost 2 frames at 60FPS. That effectively adds 25ms or so to my ping times which is annoying enough. What also concerns me is whether its going to mess with my gunnery. Aces High has code to cope with internet lag but it can't allow for monitor lag. So if the game is running two frames ahead of what I am seeing on the screen am I going to be shooting in the wrong place all the time?
Title: Re: LCD monitors and input lag
Post by: BaldEagl on July 08, 2009, 06:18:38 PM
Huh?  Any good gaming LCD has a total response time of 2-3ms.  If you buy an LCD with over 5ms response time you'll likely experience ghosting.
Title: Re: LCD monitors and input lag
Post by: AirFlyer on July 08, 2009, 06:25:49 PM
http://www.newegg.com/Product/Product.aspx?Item=N82E16824236056

That's what I use and I love it, great monitor for the price IMO.

The only complaint I have with it is that with the power cord running near my foot, it can be easy to pull out by accident.
Title: Re: LCD monitors and input lag
Post by: Greebo on July 09, 2009, 02:10:23 AM
Just to be clear, I'm not talking about response times here. The HP monitor I mentioned has a response time of 6 ms and uses RTC technology to reduce ghosting. Response times are just the time it takes each pixel to change colour.

Input lag is the time it takes the monitor to process the information it receives from the video card and display it on the screen. On some monitors this can average out at 5 ms, on others it can be over 60 ms. It isn't a constant either, the delay goes up and down all the time. The dearer monitors that do a decent job of colour reproduction seem to suffer worse input lag than the cheap ones, as they do more image processing.
Title: Re: LCD monitors and input lag
Post by: Getback on July 09, 2009, 03:45:49 AM
http://www.newegg.com/Product/Product.aspx?Item=N82E16824009167

I use something similar to this. Only this seems to be upgraded. My response time is 5ms. I tell ya, no matter what you get, and I'm sure you're thorough, you will love the large display.
Title: Re: LCD monitors and input lag
Post by: RTHolmes on July 09, 2009, 05:20:51 AM
if the monitor input lag is consistent I dont think it should make too much difference, the aircraft will feel marginally less responsive and you'll adjust your lead instinctively to compensate when shooting. from experience gunnery isnt a real problem for you. grrr!

makes me wonder about control lag too - presumably theres some latency from stick input to the flight model over USB too?
Title: Re: LCD monitors and input lag
Post by: Skuzzy on July 09, 2009, 06:37:48 AM
I feel your pain Greebo.  I am hoping my current monitor will hold on long enough so a better technology can be found for monitors.

I have yet to find an LCD monitor which will reproduce color as well as my current professional series NEC monitor does.  Any of the better LCD monitors which attempt true color reproduction are much slower than a "gaming" LCD panel.

That is the trade-off with LCD.  You want it fast, or do you want it accurate?  You cannot have both.  Not yet anyway.
Title: Re: LCD monitors and input lag
Post by: mipoikel on July 09, 2009, 01:16:25 PM
LP2475w is a good choice but if you want even better check this:

LP2480zx

http://h10010.www1.hp.com/wwpc/us/en/sm/WF05a/382087-382087-64283-72270-3884471-3648397.html

Not for gaming but for color reproduction... yes.

You can find lots of reviews of this.

http://www.macobserver.com/tmo/review/HP_DreamColor_LP2480zx_Professional_Display/

http://www.justechn.com/2008/06/10/hp-dreamcolor-lp2480zx-lcd-display
Title: Re: LCD monitors and input lag
Post by: Skuzzy on July 09, 2009, 02:02:10 PM
Better, but still limited in the visible spectrum of light it can reproduce, as compared to a pro monitor, but much better tha other LCD monitors.  It will still lag from input to display worse than a monitor.

Getting there though.  Thanks for the heads up.
Title: Re: LCD monitors and input lag
Post by: Greebo on July 09, 2009, 03:22:25 PM
The LP2480 is rather nice, but I could get five LP2475s for the same money.... :) The 2475 or similar would probably do me for the art work side, it's the lag thing that bothers me.

I can't really see why good quality LCDs must lag anyway. The problem seems to be that the screen updates every 16.6ms at 60 FPS and that the monitor can't process all the info from the video card in that time. At some point it is lagging so far behind the video card it skips a screen to catch up. What these monitors apparently need to reduce lag is more on board processing power, not a different screen technology.

Until recently NEC made a 24" LCD called the NEC 24WMGX3 for a similar price to the HP. It let you select a gaming mode which reduced the image processing the monitor did to give it much less lag but a slightly worse looking picture. Unfortunately this monitor cost too much to make and have now dropped it.

I'm not sure what to do now. An LCD monitor will give me 60 FPS instead of 85 FPS and will either lag by up to 3 frames causing possible gunnery issues in AH or will give me lousy colour reproduction for art work. Only plus points are three extra inches of screen width, a bit more desk space and lower power consumption. Overall though it seems like I'm paying out for a downgrade.
Title: Re: LCD monitors and input lag
Post by: mipoikel on July 09, 2009, 03:38:55 PM
causing possible gunnery issues in AH

Please, buy that monitor asap!  :P :devil
Title: Re: LCD monitors and input lag
Post by: Skuzzy on July 09, 2009, 04:04:32 PM
Please, buy that monitor asap!  :P :devil

ROFL!   :rofl
Title: Re: LCD monitors and input lag
Post by: Greebo on July 09, 2009, 04:19:30 PM
Can't do that.....I already miss with 90% of my rounds.  :D
Title: Re: LCD monitors and input lag
Post by: Wmaker on July 09, 2009, 05:18:25 PM
Yep,

I pretty much agree with Greebo and Skuzzy. Currently I have a rather old Samsung 950p dying on me. Heh, this thing isn't even a flatscreen CTR. :) I was on budget and ordered a Benq G2400WD 24" 16:10 widescreen for 200€. I don't do anything too colour gamut -critical stuff like Greebo and that screen has the average colour reproduction at best. I think there's a good possibility that I get dissapointed with the colours of that new LCD after using a CRT for so long. For AH it will of course be nice now that there's a widescreen support. That monitor also has 1:1 pixel ratio feature so I should be able to use other resolutions than the native if my hardware can't handle it. I can understand Greebo's dilemma very well.

Greebo have you checked this out?: http://forums.anandtech.com/messageview.aspx?catid=31&threadid=2049206  (http://forums.anandtech.com/messageview.aspx?catid=31&threadid=2049206) HP LP2475w is listed there on couple of categories...
Title: Re: LCD monitors and input lag
Post by: Greebo on July 16, 2009, 08:11:45 PM
That's a really good link Wmaker. I used it to visit all the other review sites listed there as well. In the end I found four 24 inch LCD monitors with near to zero input lag. There is the IIyama E2403WS, the Iolair MB24W, the Philips 240BW and the BenQ E or G2400 series. Unfortunately most of these are hard to find now in the UK and none of them are in a CRT's or even the HP LP2475w's class for colour reproduction.

I knew I wouldn't be really happy with any current LCD monitor so in the end I decided to have one more go at fixing my old CRT monitor. I spent a couple of hours getting the case and the EMF shielding off, then unplugging cables from the various circuit boards as I removed them while making notes how it should all go back together. Then I had a good poke round. Turned out an earth cable running from the tube to the case had a dry connection. So I made up a new cable, put the whole thing back together and now it works great again. Hopefully by the time this old thing finally packs up completely there will be a monitor just as good on the market.

Thank you to everyone for the advice and links, if nothing else I learned a lot about monitors. To anyone else looking into stuff like input lag these are the sites I found most helpful for monitor reviews:

http://www.tftcentral.co.uk/
http://forums.anandtech.com/messageview.aspx?catid=31&threadid=2049206
http://www.digitalversus.com/duels.php?ty=6&ma1=48&mo1=304&p1=2943&ma2=35&mo2=417&p2=3984&ph=12
http://www.behardware.com/html/cat/22
http://www.prad.de/en/monitore/reviews.html
Title: Re: LCD monitors and input lag
Post by: Hamltnblue on July 16, 2009, 09:45:20 PM
I seem to miss my shots because of monitor lag.  :cry.  Has nothing to do with beer, wife nag, dog peeing on leg etc.
My 24 inch LG has great color, 2 ms response and passes with high end games like Far Cry2 and Arma 2.  AHII graphic wise looks like an 80's game against them and can't be used as a reference in my opinion. Also I find that once flying and fighting, the graphic element is less important as long as there isn't a stuttering issue.
Title: Re: LCD monitors and input lag
Post by: RTHolmes on July 17, 2009, 06:57:33 AM
^not sure you're getting this, have a look at http://en.wikipedia.org/wiki/Input_lag (http://en.wikipedia.org/wiki/Input_lag).


This is an interesting article:
http://www.behardware.com/articles/632-1/lcds-images-delayed-compared-to-crts-yes.html (http://www.behardware.com/articles/632-1/lcds-images-delayed-compared-to-crts-yes.html)

suggests that you should have VSYNC ON only if the framerate never drops under 60, and triple buffering always OFF. Also got me wondering how much latency there is from my X52, uses USB2 so could be very low.

they have also reviewed the Iolair MB24W, which has an input latency of .... 0!
http://www.behardware.com/articles/712-4/lcd-david-vs-goliath-iolair-vs-dell.html (http://www.behardware.com/articles/712-4/lcd-david-vs-goliath-iolair-vs-dell.html)
Impressively it had some negative latency results, ie overall latency was lower than the CRT, presumably due to DAC processing.