OxfordBlue

probably need to compare different brands as the Benq boards update android and firmware remotely by them when connected to internet or sent by own network admin. step up from USB updating each screen manually.

best not to mirror as you wont get native resolution on both, aspect forcing may help scale, but text could look a little odd as out of native. if you can extend the desktop, and set both resolutions to the native (W10 also allows spanning of touch for later touchscreens). failing that SMARTboard only. but defeats the object of having laptops.

if looking to annotate over desktop, webpages etc. then I know the CleverTouch and Benq (and probably other android screens) have floating android toolbars that can annotate over a pc input, then just save it, benq have a snapshot key.

perhaps try to get a demo. the benq 79" has built in android with internet connectivity.

a lot depends what you want to do with it, if just teacher writing then a smartboard is great for the bigger size but if you want internet, video etc then screens are a good choice if you can afford it. Lamps less of an issue as you have the Casio laser and 10,000 hour lamps from others. which benq screens do you have? they got a lot better since the optical ones a few years back, just got an email about a 79" with android coming out.

are you bothering with the 'classroom' monitor mode?

much of 'flicker' comes from the dimming of the LED backlights, where flicker-free displays are available now.

Microsoft's minimum requirement for W8.1 is 5 point touch. Whilst may not be an issue today, with W10 rumoured to have a major upgrade in touch interaction, I would suggest to look at least hitting this minimum. 10 point touch on the latest panels is useful for 2 users.

I don't know the model, but projectors are fairly clever these days and lamp errors cause a forced shut down, so sounds like a faulty lens or focus ring. being an entry model I doubt it came with a de/re warranty, which always for schools we would recommend, but contact Optoma support for help.

Native 4k content will look great especially on bigger screen sizes. Decent scaling down to legacy sources is vital, both 1080p and WXGA. Not all 4k screens are the same.

touchscreens have many benefits over the traditional IWB but power isn't really one of them. a SMARTboard takes power off the USB at 1.5w... can't be 2kW (Promethean AFAIK is mains powered but can't think it's much) a DLP projector with an intelligent power system ranges dynamically from 60-230w. In comparison a 70" screen is 300w max, and 65" 265w max. Also to consider the usage of the projector v touchscreen, the later will likely to be left on longer as it has a wider usage than the whiteboard did. plenty of benefits, just not energy saving.

sounds like you have a DMD failure. (if it looks like iron filings) wont get any better, only worse, but you could get the DLP DMD chip replaced.

would suggesting getting it in writing specifically that their warranty covers table use. if there are no (or inadequate) fans the heat will disperse upwards through the panel, not where it's meant to... probably explains why the SMART tables cost quite a bit more than a budget 42" screen.

looks like a reference back to the BECTA days. Most projectors can be reduced in steps of brightness, or better still built in reactive eco settings. choose what's best for the classroom with lights on, no centre hot spot, and so the teacher's not looking into the projector's mirror. the new touchscreens are much brighter, and more direct close-up light than any projector can output.

hi Stuart, have you tried contacting Benq for a demo? they have a booking page at BenQ Interactive Displays OB

it's like the projector education business ten years ago; many many brands, product with similar looking spec but widely varying quality, warranty nightmares, but with experience it wasnt just about the inital price.

worth hands on demo with any screen, they are not all the same, some are cheap for a reason.... many hours right up close, so worth getting it right.

if you buy WXGA you can lock down in XGA (most models) with no loss of resolution. trying it the other way round will reduce pixels. Plus you're future proofed a bit for upgrading.

how did you get on with their recommendation?

I forwarded your thread onto BenQ, as we can't see how freezing the image is causing the laptop to sleep, the two shouldn't be related.

also check the power settings for the laptop, if it's going to sleep and timed to switch off the display, the projector isn't getting a source anymore. I've got a short throw Benq here, freeze is working if the laptop is on, if I put it to sleep then the projector goes off.

go into the menu > system setup:basic > operation settings > is auto power off set to any time? if it is try extending or disabling.

is the laptop or pc going to sleep whist the freeze is on?

is your lamp in smarteco mode? try changing it. projector is trying to save lamp life.

PowerPoint 2013? you could try this options > Advanced > uncheck " automatically extend display when presenting on a laptop or tablet" though you did mention its' when exiting full screen it's worth try.