Latitude E7240 and E7440

Woops, yes, A14. I've had it repeat keystrokes twice. It's pretty rare but not gone entirely.

 

I've since changed my theory. A long test on battery produced equally bad fan behaviour.

My latest theory is fan temperature thresholds are being tested by Dell when machines are cool, not long after boot. However after a couple of hours the whole chassis is warmed through and the ambient temp sensor (which plays a major role) is permanently above its threshold for cutting the fan.

The fan itself has very little direct influence on this ambient temperature reading so it has to run continuously to try to get it down. On my E5440 the fan doesn't even suck air from the internal cavity of the machine, air comes only from a small intake, through the heatsink and out.

On top of this on certain models and certain OS's (Windows 7, Linux) it's impossible to change these temperature thresholds, they're totally fixed. These are business machines designed to be used all day in all sorts of environments, fan thresholds should be set for these scenarios, not for a quick test in an air-conditioned lab!

I'm still mystified how thermal modes can be broken in Windows 7 using the Dell drivers, and yet work in Windows 8 without a Dell driver?!?

 

Dell does have a firmware update for the 841 on the driver page for my 7440

 

I tried to update it. But it says no 841 SSD detected.

 

Yeah I got that too. Yours may have come with a newer firmware. around 30% of the 7240s and 7440s I build at work take the firmware update. I think were deploying our 130th machine this week.

Have any of you guys repasted the cpu on either model? im debating on doing it just to do it.

 

I've just picked up an E7240 off the outlet for £700 (i5/256GB/8GB/1080p) which I'm pretty pleased with so far, it's a scratch and dent but can't see any marks on it and strangely Dell UK don't allow you to spec either the current or new Latitude 12 with a 1080p screen. I tried a new XPS 13 but while the screen was lovely, the fan noise was irritating, the QHD+ screen was too high a resolution (no 1080p option here) and it lacked ports. There seems to be very few small laptops with a decent range of ports and upgradeable parts and annoyingly Lenovo made a bit of a mess with the X240 plus it's great to have touchpad buttons.

First question was whether I could upgrade to a backlit keyboard which seems possible as long as I have the connector which I'll check, the second question I had was whether it's possible to change the touchpad to use the more old fashion scrolling using the edges rather than the multi finger scroll which I'm not keen on?

Thanks,
John

 

Yes, on a i7 7440, was an easy job, parts well designed for servicing. No big gain, lowered temp by just a few °C. It's silent with low proc. use, and am finding fan noise and temp very tolerable\as expected with high proc. use.

 

You can enable one finger vertical scrolling in the Scroll and Zoom in the Dell touchpad control panel but I can't see a horizontal one finger scroll option.

John

 

Thanks, where is that option? I know the XPS 1640 had it but I can't seem to find it on this one, I've tried disabling two finger zooming but it doesn't seem to change the options. I'm on v.8.1206.101.110 according to the control panel.

John

 

It's the bottom option on the previous version (v.8.1206.101.109). I'm running Windows 7 in case that is significant.



John