Here are a couple of other threads on this issue: http://www.surfaceforums.net/threads/has-anybody-formatted-ssd-and-clean-installed-win-8-1.10767/ http://www.surfaceforums.net/threads/clean-install-of-windows-8-1-on-sp3.9609/ For the record, I did NOT have to disable Secure Boot. Anyways, the whole process was largely uneventful. I had to disable BitLocker before I could format the partition. The only other thing of note is that, upon first boot, I did not have WiFi. Apparently the default installation of Win 8.1 Pro does not have a WiFi driver that works with the SP3. So instead I plugged into hardwired Ethernet using a USB3 to GigE adapter, for which the default installation apparently did provide a driver, as I did not have to install one--it just worked. I then ran Windows update, and it took care of everything. So I actually did not have to install a single driver manually, which was nice. Almost felt like I was using an Apple A few comments: 1) BitLocker was enabled by default after I did my clean install. 2) Benchmarks have gone up slightly, but probably not in a way that is statistically significant. On Geekbench, there are presently 199 results if you search "surface pro 3 i5 32-bit.". When I ran Geekbench on the factory default installation, my results were right in the middle of the pack. When I ran Geekbech on my clean installation, my single core score is now #2 out of 199, and my multi-core score is now #7 out of 199. So again, who knows if this is just the regular ebb and flow of benchmarks (maybe my house was colder this morning and the CPU throttled less--who knows), but I was happy to see the increase . And I always like being at the top of the benchmark pile 3) In total, there were about 3 GB of less bloat installed. For instance, there is no "MS Office" tile on the Start screen. Also, the games like Mah-Jong and Solitaire were not installed. And a handful of other things were not installed. 4) I did not yet delete the recovery partition, because I wanted to make sure everything was working first. Since the recovery partition is ~5 GB, a clean install + deleting recovery partition would net nearly 10GB of recovered space versus the factory install. Not a huge deal if you've got a 256 or 512 GB drive, but it is a pretty huge deal if you have the 64 GB i3 model. 5) You have to do a manual pairing of the Surface Pen via Bluetooth. It is simple. 6) When I ran a registry cleaner after doing Windows update and installing all of my apps, it only had to fix 42 issues. When I ran the registry cleaner on the default MS installation after doing Windows update and installing all of my apps, it had to fix about 70 issues. I assume this is because the default MS installation had .DLL files and other things that are removed/replaced by Windows update, while a clean installation never puts the old files on the system to begin with. 7) Overall it is working exactly the same as it was before I did the clean installation. So arguably the whole exercise was a waste of time. But hey, I'll take the extra SSD space and the higher benchmarks, even if I'll never notice it in real life Edit (update with the following info, also posted below): Just discovered one thing that apparently does need to be done manually. The top button on the Surface Pen was not working. I had to manually install Windows Update KB2968599, and now everything is working as expected. Not sure why that particular update was not installed by Windows Update, but I note that this update is apparently part of the Surface Pro 3 firmware/driver pack (no other Windows update is part of this), suggesting some recognition on Microsoft's behalf that this needs to be installed manually, for some reason. Anyways, all now working as expected, and was a perfectly simple fix to get the top button of the pen working.