Microsoft has flicked the switch and made Windows 7 Service Pack 1 available to all users of its flagship operating system.

The update, available via the Microsoft Download Center or Windows Update, is for the most part a collection of previously-available patches and bug fixes.

The standalone installer, available in 32-bit and 64-bit flavours, weighs in at 537MB and 903MB, respectively, but users opting to retrieve the service pack through Windows Update should see download sizes drop to as little as 44MB depending on which updates have been previously installed.

Taken the plunge? Share your SP1 upgrade experience in the HEXUS.community forums. If you're treading carefully, Microsoft has a selection of tips and recommendations for installing SP1 on its official blog, and we've included all of the update's notable features below.

Notable Changes in Windows 7 and Windows Server 2008 R2 Service Pack 1

Changes specific to Windows Server 2008 R2

Dynamic Memory

Constraints on the allocation of physical memory represents one of the greatest challenges organizations face as they adopt new virtualization technology and consolidate their infrastructure. With Dynamic Memory, an enhancement to Hyper-V™ introduced in Windows Server 2008 R2 SP1, organizations can now make the most efficient use of available physical memory, allowing them to realize the greatest possible potential from their virtualization resources. Dynamic Memory allows for memory on a host machine to be pooled and dynamically distributed to virtual machines as necessary. Memory is dynamically added or removed based on current workloads, and is done so without service interruption.

Virtual machines running a wide variety of operating systems can use Dynamic Memory; for a complete list, see the “Dynamic Memory Evaluation Guide” at http://go.microsoft.com/fwlink/?LinkId=192444. The guide also discusses Dynamic Memory settings and usage in detail.

Microsoft RemoteFX

Businesses are increasingly looking to leverage the efficiency and cost savings that can come from a virtualized desktop infrastructure. With the addition of Microsoft RemoteFX in Windows Server 2008 R2 SP1, a new set of remote user experience capabilities that enable a media-rich user environment for virtual desktops, session-based desktops and remote applications is introduced. Harnessing the power of virtualized graphics resources, RemoteFX can be deployed to a range of thick and thin client devices, enabling cost-effective, local-like access to graphics-intensive applications and a broad array of end user peripherals, improving productivity of remote users.

RemoteFX can function independently from specific graphics stacks and supports any screen content, including today’s most advanced applications and rich content (including Silverlight and Adobe Flash), ensuring that end users maintain a rich, local-like desktop experience even in a virtualized thin-client environment.

RemoteFX also adds mainstream USB device support to virtual desktop computing, including support for USB drives, cameras and PDAs connected to the client device. RemoteFX also provides a platform for hardware and software partners to enhance RemoteFX capabilities in a variety of possible host, client and network configurations.

To use RemoteFX, the virtualization server must be running Windows Server 2008 R2 with SP1, the virtual machine must be running Windows 7 Enterprise with SP1 or Windows 7 Ultimate with SP1, and the remote client computer must be running either Windows Server 2008 R2 with SP1 or Windows 7 with SP1. To connect to the virtual machine, the remote client computer requires an updated version of Remote Desktop Services (included in the service pack for all editions of Windows 7).

Enhancements to scalability and high availability when using DirectAccess

DirectAccess is a new feature in the Windows 7 and Windows Server 2008 R2 operating systems that gives users the experience of being seamlessly connected to their corporate network any time they have Internet access. In Windows Server 2008 R2 SP1, improvements have been made to enhance scalability and high availability when using DirectAccess, through the addition of support for 6to4 and ISATAP addresses when using DirectAccess in conjunction with Network Load Balancing (NLB).

Support for Managed Service Accounts (MSAs) in secure branch office scenarios

SP1 enables enhanced support for managed service accounts (MSAs) to be used on domain-member services located in perimeter networks (also known as DMZs or extranets).

Support for increased volume of authentication traffic on domain controllers connected to high-latency networks

As a greater volume of IT infrastructure migrates to cloud-based services, there is a need for higher thresholds of authentication traffic to domain controllers located on high-latency networks (such as the public Internet). SP1 allows for more granular control of the maximum number of possible concurrent connections to a domain controller, enabling a greater degree of performance tuning for service providers.

Enhancements to Failover Clustering with Storage

SP1 enables enhanced support for how Failover Clustering works with storage that is not visible for all cluster nodes. In SP1, improvements have been made to the Cluster Validation and multiple Failover Cluster Manager wizards to allow workloads to use disks that are shared between a subset of cluster nodes.

Changes specific to Windows 7

Additional support for communication with third-party federation services

Additional support has been added to allow Windows 7 clients to effectively communicate with third-party identity federation services (those supporting the WS-Federation passive profile protocol). This change enhances platform interoperability, and improves the ability to communicate identity and authentication information between organizations.

Improved HDMI audio device performance

A small percentage of users have reported issues in which the connection between computers running Windows 7 and HDMI audio devices can be lost after system reboots. Updates have been incorporated into SP1 to ensure that connections between Windows 7 computers and HDMI audio devices are consistently maintained.

Corrected behavior when printing mixed-orientation XPS documents

Prior to the release of SP1, some customers have reported difficulty when printing mixed-orientation XPS documents (documents containing pages in both portrait and landscape orientation) using the XPS Viewer, resulting in all pages being printed entirely in either portrait or landscape mode. This issue has been addressed in SP1, allowing users to correctly print mixed-orientation documents using the XPS Viewer.

Changes common to both client and server platforms

Change to behavior of “Restore previous folders at logon” functionality

SP1 changes the behavior of the “Restore previous folders at logon” function available in the Folder Options Explorer dialog. Prior to SP1, previous folders would be restored in a cascaded position based on the location of the most recently active folder. That behavior changes in SP1 so that all folders are restored to their previous positions.

Enhanced support for additional identities in RRAS and IPsec

Support for additional identification types has been added to the Identification field in the IKEv2 authentication protocol. This allows for a variety of additional forms of identification (such as E-mail ID or Certificate Subject) to be used when performing authentication using the IKEv2 protocol.

Support for Advanced Vector Extensions (AVX)

There has always been a growing need for ever more computing power and as usage models change, processors instruction set architectures evolve to support these growing demands. Advanced Vector Extensions (AVX) is a 256 bit instruction set extension for processors. AVX is designed to allow for improved performance for applications that are floating point intensive. Support for AVX is a part of SP1 to allow applications to fully utilize the new instruction set and register extensions.

Improved Support for Advanced Format (512e) Storage Devices

SP1 introduces a number of key enhancements to improve support of recently introduced storage devices with a 4KB physical sector size (commonly referred to as "Advanced Format"). These enhancements include functionality fixes, improved performance, and updated storage drivers which provide applications the ability to retrieve information as to the physical sector size of storage device. More information on these enhancements is detailed in Microsoft KB 982018.