Vizio VO22L HDTV10A review: input lag and upscaling tested using the piLagTesterPRO

This 720p TV from 2008 is rather mediocre, with variable input lag, aliasing, and in general very little to recommend it for gaming, retro or otherwise. 

Overview/Image quality

45 degree line @720p

At native resolution (720p) this TV doesn't look that great - it crops 80 pixels off the left and right side of the screen (and also about 5 off the top and bottom). Who knows what the actual resolution of the screen is, as after throwing away that many pixels the screen still has some aliasing (see photo).  Edit: if you set it to 1024x768 it has zero cropping and almost zero aliasing, so I suspect that's the native resolution - which is to say this is really a computer monitor panel, pretending (poorly) to be a 720p TV.

Surprisingly, if you give it 1080p it actually looks smoother than 720p, with less jaggies, though of course any fine detail is blurred away, since the panel resolution is fairly close to 720p. 

I briefly tried using it as a cheap computer monitor, and it's very poorly suited for that due to the massive cropping. It also over-sharpens the input, though in fairness I didn't bother to mess with image settings to see if I could improve the picture further once it became clear that the 80 pixels of cropping could not be adjusted away. (note: If I had selected 1024x768 instead of the reported native resolution of 720p it probably would have looked better).

It has all the standard inputs, including 2 HDMI, VGA, and yPbPr. I only tested HDMI. 

Input Lag

This display does not have a game mode; just a game 'color' preset that does not impact lag at all. I toggled all the display quality settings and did not see a consistent effect on lag, however the tests reported are with every "enhancement" set to off. I used a piLagTesterPRO to measure input lag. This device sends a frame of video over HDMI and measures how long it takes to display it.

Complicating things significantly, this is yet another display that does not actually sync to the input signal - instead it fills its own internal frame buffer from the video input and then draws that with a fixed additional delay that is randomly determined each time you turn on the set or switch inputs. It does set the refresh rate properly based on the input refresh rate (60hz and 59.94hz), so there's no drift/dropped frames, but, to take one example, input lag for 720p can vary from 20.4ms to 35.5ms. What you get seems to be entirely up to chance. I've elected to report the average lag values here, since that seems fairest, but there's no right answer; for more discussion of this issue see the above link.

Full Test Results 

I report two kinds of values. 1st response measures how long it takes for the TV to start responding (I use a 5% change in display brightness). This overly optimistic value doesn't tell how long it takes to see anything useful, but matches what other reviewers call input lag. full response is a more realistic measure of lag, and requires the display to reach 80% of it's final brightness. This combines both input lag and response time, and is closer to what you would actually experience in a game.

test location:	top		bottom
Resolution	1st response	full response	1st response	full response	scan out	response time	rf full
480i	61.0	79.0	76.0	94.0	15.0	18.0	18.0
480p	28.0	46.0	43.0	61.0	15.0	18.0	18.0
720p	28.0	46.0	43.0	61.0	15.0	18.0	18.0
1080p	28.0	46.0	43.0	61.0	15.0	18.0	18.0

 

There's a lot of repeats here - every resolution is the same except 480i, which is 33ms slower (suspiciously, that's exactly the length of two frames of video).  I also tested 1024x768, which was no faster than the official native resolution).

Interestingly, even upscaling to 1080p doesn't slow the panel down relative to its "native" resolution. 

The scan out appears to be slightly faster than the refresh rate, suggesting that once the panel starts drawing it actually goes from top to bottom slightly faster than the data was transmitted. 

Results compared to other displays

To allow quick comparison between many display I've summarized the results across all the displays I've personally tested with the piLagTester Pro.  Min lag is the first response at the top of the screen, real lag is the full response at the bottom. 

Display	Year made	Native Res	native min lag	480i real lag	480p real lag	720p real lag	1080p real lag	response time	scan out
Dell U2410 (game)	2010	1080p	4.0	62.2	28.3	26.5	26.5	6.00	16.20
Dell U2410 (sRGB)	2010	1080p	20.5	62.4	45.0	43.1	43.1	6.13	16.13
Sony 40VL130 (game)	2008	1080p	22.8	66.3	49.0	47.3	47.3	9.08	15.43
Sony 40S20L1	2007	720p	48.4	90.1	72.9	73.4		9.60	14.00
Emprex HD 3202	2007	720p	27.0	126.0	51.0	50.0		8.50	15.00
LG 42LC2D	2006	720p	28.3	54.6	50.8	50.4		6.30	15.95
Vizio VO370M	2010	1080p	2.5	83.0	49.0	47.0	24.3	5.47	15.67
Philips 42PFL3603D/F7	2009	1080p	29.0	84.0	50.0	50.0	50.0	5.00	16.00
Samsung S27C230	2014	1080p	2.9		36.6	36.1	37.0	18.25	14.97
LG 47LW6500-UA	2012	1080p	66.6	149.7	149.0	81.7	80.9	2.27	11.83
Vizio VO22L HDTV10A	2008	720p	28.0	94.0	61.0	61.0	61.0	18.00	15.00

If it weren't for the variable lag this TV would be pretty decent, since recall that on a good day it can start to respond after only 20ms , better than many TVs listed here. But the average lag is more representative, and once you add in the response time this TV ranks way below average.  The 480i results are particularly bad, too. 

Conclusion

This would be a poor choice for gaming of any type, particularly retro gaming. Although I didn't bother to watch video on it, my experience using it as a computer monitor suggests the image quality isn't great for natural scenes either.  I would avoid this as a monitor. Interestingly, I also tested a 2010 mid-range Vizio (Vizio VO370M) and had much better experience with that, so I guess their tech got better quick! Note that this Vizio and the VO370M don't properly sync with the input, suggesting that might be a common design choice of Vizio for that era.

Other models (to avoid)

I tested the V022L HDTV10A  model, which is the tiny 22" version. There appears to be two versions: HDTV10A, which is roughly 720p, and FHDTV10A which is the 1080p version.  Based similarities in their names, I suspect that the VO32L and VO37L HDTV10A  would perform similarly, just with bigger pixels. However, I've made no efforts to check if their specs exactly match the V022L HDTV10A , so that's only a quick guess.