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How to reduce unnecessary drivers in Windows 10
Ed Tittel
Nov 5, 2015 5:24 AM
PT
Over time on Windows systems, it's inevitable that old device drivers are supplanted by new ones. Even on systems
where drivers aren't rigorously maintained, Windows Update will typically update or replace, on average, a dozen
drivers annually.
Those who pursue driver currency more vigorously may use tools like the Intel Driver Update utility, GeForce
Experience (an Nvidia tool that checks graphics, sound and 3D drivers) or outright driver management tools such as
eSupport's DriverAgent or Slimware Utilities’ Driver Update to check and update drivers on their Windows PCs
(whether Windows 7, 8 or 10.) The Intel and Nvidia offerings concentrate on devices they make, whereas generalpurpose driver update tools like those just mentioned from eSupport and Slimware Utilities check all of them – and
point you at drivers in need of updating, with varying degrees of help and support in getting them installed.
What happens when you install a Windows Driver?
Installing a Windows Driver is actually a fascinating process, and involves a lot of behind-the-scenes action in
Windows. For this discussion I'm going to stick to so-called Plug and Play (PnP) devices, which are built to announce
themselves to Windows so that it can at least assist in finding a device driver to use, if not find the latest and greatest
instance of its kind. My information comes courtesy of Mark Russinovich and David Solomon's terrific book Windows
Internals (6th edition in two volumes, as of this writing):
1. A bus driver informs the PnP manager about a device it discovers during enumeration using a device instance
identifier (DIID).
2. The PnP manager checks the registry for a corresponding function driver. When it fails to find one, it tells the
user-mode PnP manager about that device using its DIID.
3. The user-mode PnP manager tried to perform an automatic install without user input or intervention. For those
installers that involve posting of dialog boxes that require user input, the PnP manager will execute a Hardware
Installation Wizard to oversee such task(s) if the logged-in user has admin privileges. (If not, this activity will be
deferred until an admin-level user next logs in.)
4. The Hardware Installation Wizard uses Setup and CfgMgr (Configuration Manager) API functions to locate INF
files that correspond to drivers that are compatible with the detected device. This might involve accessing the
Microsoft device databases to look for such files, or accessing such files from the local file system (or media
like a CD or DVD) at the user's direction.
5. Installation proceeds in two steps: (1) The third-party driver installer imports a driver package into the driver
store, and (2) the OS performs the actual driver installation, using the Drvinst.exe process (the executable for
which resides in %SystemRoot%\System32\). As part of that process, .inf and .cat files are deposited in the
driver store associated with a DIID that takes the form of oemnnn.inf, where nnn represents a one- to threedigit decimal number
It's important to note that the process documented says nothing about cleaning up older versions of drivers already
present in the Windows driver store (in the %SystemRoot%\System32\DriverStore directory). The focus of this article
is on investigating the contents of that driver store, and removing older and/or obsolete items to reduce its on-disk
footprint.
Warning!
There's an important downside to consider when removing elements from the driver store. If you remove all drivers
except for the most recent one(s), you will not be able to use the Roll back driver option in the Properties window for
the related device in Device Manager to revert to an earlier version of the driver, should the current one prove
unstable. A more conservative approach to pruning your driver store might therefore be to keep the two most current
drivers for any given device, rather than only the most current one. I myself do not follow this approach, except for
drivers that are updated frequently or when using a beta driver. When only one driver is present for a device, the Roll
Back Driver button is greyed out and inaccessible (see Figure 1).
Figure 1: When only one driver version is in the
DriverStore, roll back is not an available option.
Getting the lowdown on device drivers in Windows 10
For all modern Windows versions (Vista and newer) there's an
excellent tool available to explicitly observe and manage the
Windows driver store. The tool comes from CodePlex,
Microsoft's free, open source software and source code
repository, and it's called DriverStore Explorer (aka RAPR.exe).
To forestall inevitable questions, version 0.5 dated December 30,
2012 is indeed the most current version as of this writing, and it
works quite well with Windows 10, which it predates by almost
three years.
To operate on the driver store, you must run RAPR.exe with
administrative privileges (right-click the filename and then select
Run as administrator from the resulting pop-up menu). Next, you
must enumerate the items in the driver store, which produces a
display that looks similar to Figure 2. (Driver Store Explorer will show the drivers present for the devices on your PC
rather than for the devices present on the machine whence this screenshot originated, my Surface Pro 3.)
Figure 2: That's it! My cleaned-up Surface Pro 3 Driver Store includes only 33 drivers.
To give you an idea of what can happen to this repository for driver files, I've seen the total item count on this same
machine go as high as 112, of which over 30 items were duplicated Intel drivers of one sort or another. If you click on
any of the column heads shown in this display, the listing will re-sort itself to match.
When pruning drivers, I usually click on Driver Class and then look for multiple instances of the same driver on a
class-by-class basis. To attempt to remove them, one need only click the check box at the left as shown in Figure 2,
then click the Delete Package button at the right.
Here's the good news about working with RAPR: it won't let you delete any drivers that Windows is actually using
unless you over-ride the program and use the Force Deletion button explicitly. The only times I've ever used this
capability with the program is when multiple sources of good advice have urged removal of a bad or questionable
driver so that it can be replaced with a different, working, and older version.
Figure 3 shows a short before and after sequence to illustrate what typical clean-ups involve.
Figure 3a: Duplicate System devices and USB controller
entries appear on my Lenovo X220T.
Figure 3b: After pruning, only the newer instances for each
device type appear.
When you consider that drivers for a typical graphics adapter
consume between 200 and 400 MB of disk space, and that most devices require at least 2-4 MB at a minimum,
getting rid of unwanted entries can really free up some room.
When is Driver Store clean-up action needed?
An old saying on the Internet regarding system optimization and cleaning earns the YMMV acronym (Your Mileage
May Vary). It means that different systems will inevitably exhibit different behaviors, values and so forth. With that
caveat in mind, take a look at the properties for your DriverStore directory: if it's over 1 GB in size, I'd fire up RAPR
and see what it can find; if it's over 2 or 3 GB, you'll definitely want to see what's in there and get rid of what you no
longer need or want. I've seen some instances where the folder's size exceeded 4 GB, and read about some cases
where it topped 10 GB. Trust me: you don't want to let things go that far.
The worst offenders I've run into include the various Intel chipset update utilities (e.g., the various Intel Chipset Device
Software packages, often called "INF Update Utility") and the Nvidia drivers. Intel's tools seem particularly prone to
depositing dozens of copies of the same driver in the driver store.
Note: For whatever reason, if you have multiple instances of devices on (or in) your PC, you must indeed have a
separate copy of a driver package (oemnnn.inf) for each one – that's why you cannot always remove what might look
like unnecessary duplicates of the same driver on a PC. But high counts of the same driver, or worse, high counts of
multiple versions of drivers for the same device, usually warrant clean-up.
With Nvidia display drivers typically consuming 400+ MB per copy (or version), keeping older drivers around is quite
literally a waste of space. You can keep two versions for safety if you like, but there's no reason to have more than
that in the driver store. (Before I started doing regular clean-ups myself, I might find a dozen or more Nvidia display
drivers on a PC with a one-to two-year-old OS install running.)
Because you have to work at it to hurt yourself using RAPR, you needn't feel compelled to make a restore point before
cleaning up your driver store. But because I'm a "belt-and-suspenders" kind of guy, I've gotten in that habit just in
case I accidentally remove something it turns out I really need. You can always reload that restore point from the
repair/recovery media for your OS if you wind up with a failing or unbootable machine after a too-aggressive cleanup. Who knows? It could come in handy. With a backup you can clean up whatever you want, whenever you want
without fear.