nkedel

The E5470 is officially limited to 16GB, and is not sold with 32GB (it was cheaper to buy it with 8GB and upgrade it to 32GB). I can 100% confirm that it works with 32GB, because that's the machine I'm typing on now.

I've been very happy with mine for the past year, although I'm loving the brighter and wide gamut 4K screen on my new XPS, and it's a bit faster.

The E5480 officially supports 32GB. I don't see any 32GB configurations on the public/retail web site, but it's a configuration option on the Premier site, and if you don't have access to Premier, should be available fully configured via phone agents (although it's much cheaper to buying it with 4GB or 8GB and upgrading it yourself, and these are relatively easy systems to open up. Not as nice as the two generations with the "single screw bottom panel" but it's just like 8 phillips screws around the edge and nothing fiddly)

One thing to be aware of with both the E5470 and E5480 is that they are configured with a reduced TDP of 35W for the CPU out of the box. This can be brought back up to full with Intel XTU (or various other tools), although in practice it's kind of trading higher peak performance for more throttling. The cooling in those systems is pretty good, but not comparable to the dual fan systems

The Lenovo T460p and T470p both support 32GB.

Going over 32GB still requires a 4-slot monster, of course. No word yet on when 32GB laptop SO-DIMMs will be out, or whether the current-generation CPUs will support it when they do.

SuperFlyBoy

I only bought 32GB ECC RAM with my 7510, still trying to configure it as my older machine - but taking too long...

Main thing is a good expandable dock where you do not need to fumble with cables.

However, also like the XPS-style screen with minimal frame...

nkedel

Sadly, one of the few big changes in the Kaby Lake generation is that for the Latitude models like the E5480, they finally retired the E-port dock. The WD-15 works reasonably well on my XPS, but I really like the E-dock on my E5470.

Ditto. I wish there were a happy medium (non-compromised keyboard, more like the latitude, 90W PSU rather than the 130W monster, full docking, and real internal ethernet port) but as it stands, I've got a primary machine that absolutely cranks for day to day stuff, and the E5470 for a more Linux-friendly and more portable secondary machine.

StuckInYYZ

On a slightly different note, has anyone had any experience with non-Dell laptops? Asus or MSI or Aorus? Does powering it up first or plugging it in afterwards work any better? I'm finding it hard to believe that the laptops are pulling full power the whole time.

nkedel

I'm entirely unfamiliar with Aorus, and from what I've seen of MSI and Asus, unlike Dell/Lenovo they are much less consistent about using only one or two connectors and a single voltage than the enterprise manufacturers (Dell/Lenovo, and anecdotally, HP.)

The Lenovo Thinkpad models I've tried behaves much like Dell does -- will work on lower wattages, but throttle considerably. The one exception was the W520 and W530 which were both sold with a 180W supply, but which (in a small-GPU configuration that was only about 100W for CPU+GPU) ran perfectly well un-throttled with the 135W supply which came with the W510 and some of their docks.

Still throttled, quite badly, with the T-series 90W supplies. Haven't been able to test that on a T460p/W540 or newer.

StuckInYYZ

I've noticed many older generation laptops (mostly non big 3) were inconsistent, but gaming laptops are a new beast for me. I just find myself staring at the screen for longer lately and a little bigger screen would help with the strain... To be able to cut back and game a little would be great.

StuckInYYZ

So has anyone tried plugging in a higher powered laptop into the system as of late? I'm surprised that this is still an unknown factor.

nkedel

Huh?

Airplanes are still limited to (typically) 75W, although sometimes 90W adapters will work. This is unlikely to change, as it's an airline-industry standard.

In terms of level of throttling, the latest (Kaby Lake) machines from Dell still throttle with a smaller power supply. I haven't used a current generation Lenovo.

One pleasant change is that my latest personal laptop (the Dell XPS 15 9560, which is basically the same as the Precision M5520, just with a consumer/gaming GPU) has really impressive battery life even with the HiDPI screen -- between my internal battery (a "right at the legal limit for flights" 97W/Hr) and an external Dell "power companion," I think I was at about 8-9 hours and might tbe a big over, having been too tired to remember to charge either between the long car ride on Monday and a JFK-SFO flght yesterday.

It does throttle a bit when running from the power companion (as it would with a 65W or 90W adapter) but it seems a bit less noticeable with the newer processor.

A more modest configuration (16GB rather than 32GB, non-HiDPI screen, and a less power hungry M.2 SATA SSD rather than NVMe SSD) would probably have a truly impressive battery life.

KRSW

Has anyone tried yanking the battery out of the laptop? It's been awhile since I've taken a full-blown laptop on the road (Yoga 710s / 910s have been my road laptop of choice lately, remoting back to the home office if I need more horsepower), but I remember yanking the battery sometimes did the trick.

nkedel

Relatively few current models still have removable batteries.

For ones that still do (or older models), I wonder if there's some way to get the peak current draw on a kill-a-watt or something like. That said, I doubt it would work on many of these machines -- for the Dell 130W and Lenovo 135W supplies, the adapter will trip the in-seat circuit breaker as soon as it's plugged in even without a machine attached.

StuckInYYZ

I was actually more curious if any has tried plugging in the 135w or 180w power adapters into the seats and seeing if they are still functional (even if it's only for charging). Or if anyone has figured out how to throttle the laptop to the point where it's not going to trip the fuse.

nkedel

At least in the case of the Dell 130W models, they haven't come out with a new 130W supply model since late 2013. They trip instantly with or without a computer plugged into them; I've never tried the bulkier old-style PA-4E 130W supplies, but I'd be really surprised if they didn't also trip instantly.

The same was true of the older 135W/170W Lenovo models as used with the W510-W530.

I'm not sure whether the higher-wattage Lenovos (W540 through P51, and higher configs of the T460p/T470p) have gone to a newer adapter; if they have, it would be interesting to see if someone has had experience with that.

StuckInYYZ

I have a few co-workers with W series Lenovo's but none of them are taking any flights any time soon. My next trip is next month, If any of them take any trips, I'll see if they can test and report back.

lpeterman

Like others on the forum, I have the problem with my Dell XPS 15 (9550) with 130 watt power supply.

I did some experimenting and found with no connection to the computer, when plugged in, the power supply does indeed draw approximately 0.92 amps, or about 110 watts. This lasts less than 2 seconds.

I assume the charger has some sort of capacitor for current regulation which charges immediately when plugged in and trips the circuit breaker(s).

Next I installed a 100 watt incandescent light bulb is series with the hot lead of the 120 v line. Plug in current dropped to 0.28 amps and bulb was lit ( not 100 watt lit ) and went out after about 2-3 seconds, when almost full power was delivered to the computer.

I have ordered some NTC thermistors to replace the light bulb and fully expect them to work.

I have a DFW - HKG trip on Friday, but do not expect the thermistors to be
available in time for this trip. So will use the power outlet by each of the doors on the 77W that the cleaning crews use to plug in the vacuum cleaners. From seat 1A, the outlet is just a couple feet away!

docbert

Tried my Precision 5510 (basically the same as an XPS 15) and it's 130W power supply on a United flight a few days ago, and it worked!

Previously I hadn't even been able to plug in the power supply without it tripping, but this time I was able to plug in the PS, and then connect the PS to the computer, and it stayed up the whole time.

This was on an A320 with the newer seats, so no idea if they changed something during the fitting of those seats or what.