Rugged laptops have all sorts of downsides, and most have loud fans. Have you considered a fanless computer hard mounted in your boat? 

1) Choose a fanless mini desktop with lots of cooling, something like this that runs on 12 volts, that can be mounted using velcro under the nav table of most boats. (example, I don't use this specific model)

https://www.amazon.com/Kingdel-Nettop-Window-Intel-Graphics/dp/B07RKLT55P/ref=sr_1_14?keywords=kingdel+i5+fanless&qid=1571932572&s=electronics&sr=1-14

2) Choose a display you can place on a mount (I use this specific touch display with Expedition software, works great)

https://www.amazon.com/gp/product/B07P3ZSXJ1/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

3) And then add a wireless keyboard (the smaller the better) and wireless (or wired) mouse. I use the keypad below plus a spare wired mouse I had hanging around.

https://www.amazon.com/gp/product/B00ZOPVSKW/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

Because the computer and display are hard mounted at the nav station, this (i) is drop resistant / does not need to be marine hardened  (ii) takes up a fraction of the space of a laptop (iii) is reliably available when you want to use it (iv) hidden wiring can easily be added to connect to your boat electronics if you desire (v) most now have two display ports so you can also add a large display on a wall in your boat, if you want to play movies (iv) no fan-noise, as there is no fan and (12 v) means no need for an inverter to power it.

One negative - unlike a laptop there is no built in battery and auto-shutdown, so there is no graceful shutdown if you turn off your boat battery without first turning off the computer. Also, if your engine starter is connected to the same battery, starting your boat engine will likely drop the voltage and reboot the computer. (see the discussion on 12v-12v chargers, that allow you to set up an isolated battery for your computer, or isolate your starter battery & starter, from your house battery and house loads)

@dan-corcoran

Dan, thanks, that's a great idea, hadn't thought about a stand-alone, the price is right as well.  I might get away with a tablet to take ashore for internet cafe's in the Carribean. Again, thanks for your input. 

I have an older but still perfectly functioning tablet as well, that is handy when my smartphone display isn't as big as a I would like (for example reading detailed instructions on how to apply paint, programming DC-DC converters, and reading big documents for sailboat races.

But I still find myself just as happy taking my phone ashore for most every other task a tablet can handle.

And both devices immensely frustrate me when I have to enter information (as opposed to read it). Nothing compares to having a computer when you want to write emails, manage task lists, aggresively check many weather sources, or do navigation tasks (I use Expedition connected to my boats GPS, speed, wind, etc.)

I can certainly live without a computer on my boat, but I am sure glad to have what I have vs. trying to use a laptop computer in an uneven or crowded space down below. 

Of the three (smartphone, tablet, Windows 10 in any style with keyboard), I would give up the tablet first. 

If you're going to go the "desktop" computer route I'm a big fan of the Intel NUC series of computers.  For about $500 I just recently bought one of these.  It's quick, quiet, well made and quite durable.   

There's a ton of options out there in set-top style computers and I've experimented with several.  I felt I was doing more kissing of frogs than anything until I bit the bullet and went with the NUC.  I have four of them in service between the boat and home and I'm very pleased with them.  The oldest of them is about six years and still kicking.   

Ben

@dan-corcoran

I agree, I have a keyboard for my iPad but don't use it that much.  I usually default to my desktops. 

I just looked at Expedition software, looks interesting, I have been using Navionics on my iPad but looking at all sources for the boat.  I just retired from the merchant marine, so I'm a bit spoiled when it comes to electronics, my last ship had the latest and greatest.  Going it alone has been a shock; the price tags on some of the gear blows me away.  I wanted to go with AIS "A", but the Furuno model I looked at was five grand.

NUC - Looks good. How do you get around the 19v requirement, a voltage converter?  Do the engine starts bother it?   Is there a fan?  (I am a big fan, of fan-less, absolutely silent computers, at home and on the boat)

Navonics works well, even not attached to boat sensors. I have been using it on my smartphone to answer what-if questions ever since the version of Active Captain I loved got replaced. I believe via Signal K and possibly other methods, you can bring the information into your iPad. Perhaps, if you investigate it further, you may find a way to get Navonics or a competitor to wirelessly use your boat sensor data.

I have Expedition to help me in calibrating my instruments and doing weather routing underway. It talks to my B&G suite via a hardwired ethernet connection. I have not yet developed enough proficiency in it to accomplish these tasks. The North U on-line training was key to getting me to some proficiency and I highly recommend it.

Nobeltec recommends Intel NUCs for running the TimeZero PC navigation system I plan to set up on Gizmo, and the refurb NUC 7i5BNK Ben S linked to at Amazon looks like a great deal. In fact, I just purchased one, specs here:

https://www.intel.com/content/dam/www/public/us/en/documents/product-briefs/nuc-kit-nuc7i5bnh-nuc7i5bnk-brief.pdf

It can supposedly run on 12 to 19 volts DC, but maybe it would be wise to use a DC-DC converter like this?

https://www.amazon.com/uxcell-Converter-Regulator-Waterproof-Transformer/dp/B01H97ETP8

@ben-ellison

Thanks, Ben,  I'll most likely go with the NUC as well.

@ben-ellison

That sort of DC-DC converter is good.

Nuc is good. Fanless is better; sometimes fans suck in condensation when the boat is damp... Dried salt on everything keeps things damp. Put it up forward. We sell complete fanless systems and the time zero and olex software options at navroc.com which is helpful for those who are not big into computer tinkering. If you have nmea2000 equipment, connect with a actisense usb adaptor. Otherwise ethernet and/or nmea0183.

If your laptop is perfectly dry location it might be OK, like on a big ship bridge. Small boats, one drop of water in the wrong spot on a laptop keyboard and it might be done for.

@jasonphilbrook

Thanks, Jason. My boat is quite dry -- maybe the balsa coring, plus no wet fishermen coming in from the deck 😉 -- and a Mac Mini survived fine for 8 years. But you're certainly doing some interesting work at NavRoc:

http://navroc.com/

A well-know offshore navigator suggested refurbished Dell "rugged" laptops. Some come from police departments that upgraded with Homeland Security funding when the old warranty expired. Taxpayer burden can be your gain.

A quick search turned up several sources - for instance the Latitude E6420 XFR is IP-65 certified and available for $500 - $800 depending on options.

I personally use a five-year-old MacBook Pro. He laughs at me since I can't run Expedition.

I suggest you to buy Surface Pro 4, its a best marine laptop so far, its really too easy to use on boat, its battery life is great, I bought it 6 months ago from Reecoupons, but now I also saw it on Christmas sale on there, I suggest you buy it without wasting any time. 

I might get away with a tablet to take ashore for internet cafe's in the Carribean. Again, thanks for your input.