Surface Pro 3 Slow WiFi - 72Mbps Max (driver)

It would also be worth noting specifically what problem you are having as there seems to be more than one getting conflated here. There's dropping/limited connections but also slow link speed, for example. 

I have a i5 256 SP3 with poor link speed (<72mbps) to an AC router, but not the dropping / limited connection issue. 

panicsteve.....When did you get your SP3?

There is another thread compiling LOT # with Surfaces having overheating issues, Lot 1428 and 1429 seem to be popular.

The lot # is on your box.

I had the original i5 128gb model and then support asked me to return it, then I got the i5 256gb model a month later I think and still has the same problem.  the i7 models came later so it may have an improved setup maybe.

It would also be worth noting specifically what problem you are having as there seems to be more than one getting conflated here. There's dropping/limited connections but also slow link speed, for example. 

I have a i5 256 SP3 with poor link speed (<72mbps) to an AC router, but not the dropping / limited connection issue.

If in fact , the problem is connected standby, and I suspect you are correct, Mosoft has a big problem with these units, but it's not a Microsoft Problem and it's not a Wifi Problem, it's an Intel Problem.  Connected standy works flawlessly on Atom Powered devices that go back two chip generations.  Instant On, Instant Off - Always connected in a low power state.  On my Clover Trail Tablet, when close the cover, the tablet sleeps instantly - When I open the cover it lights up instantly - and every thing is up to date.  That's not the case with my SP3 - I have to bang keys and press the power switch to get it to turn on after any length of sleep.

I have an SP2 with a Haswell i5 and 8GB Ram, but no connected standby because connected standby was never supported in the Core iX Haswell Architecture.   For the SP3 - Intel tweaked the Core i3,5 & 7 to provide connected standby functionality.  This tweak is where I think the problem must be.

The fact that MS has been so silent on this is completely unacceptable and inexcusable but I suspect there is a a hardware flaw at chip level and the symptom shows up in the WiFi because of connected standby hardware issues.

If my theory is correct Intel, doesn't know to fix it, so a recall will do nothing.  No Driver is going to fix this one and MS Needs Intel to fix it because it's not a Marvel Network adapter Problem, it's not a driver problem, it's an Intel Processor problem.........

Has anyone narrowed the wifi problem down to a particular SP3 model?  I have the 512gb i7 model relesed 01 August, and after setting my router to broadcast a 5ghz SSID I have had absolutely no wifi isuses.  866.5mbps connection, no drops, no standby issues, etc...  So, apparently there are cases where the SP3 is working correctly, with tweaks to other devices (i.e. router config). 

A general poll to readers to narrown down model and manufacture/production period:

What's your SP3 model...and what month did you receive it?

Mine:  SP3, 512gb hdd, 8gb ram, i7.......received August 04, 2014......no longer having wifi issues