This review contains the technical specifics for the MSI K9N Diamond (MS 7226) mainboard.  If you believe any of the information posted below is inaccurate please contact me.

The MSI K9N Diamond was released by Micro Star International in June 2006.  The first bios release (v1.0) is dated August 18, 2006.  The MSI K9N Diamond is the current AMD AM2 high-end mainboard from Micro Star International's K9N line of mainboards.  It is currently priced at about $170 USD, making it one of the cheapest nForce 590 SLI motherboards available.

What's in the Box.  Here is what I found in the box:

• A clear plastic tray covering the top of the mainboard
• MSI K9N Diamond (MS 7226) v1.1 mainboard
• A black foam sheet on the bottom of the mainboard
• Quick User's Manual, v1.0
• Quick Guide, G52-72262X1-L03
• Drivers & Utilities CD
• Sound Blaster Live 24-bit Installation CD
• Rounded Ultra/133 IDE Cable (red)
• Rounded Floppy Cable (red)
• 6x Serial ATA Cables (red, 4 straight, 2 elbow)
• 3x Molex to Serial ATA Power Cables
• USB D-Bracket2
• IEEE 1394 Bracket
• SLI Bridge
• SLI Bridge Secure Bracket
• I/O Back Shield

Mainboard Layout.  The MSI K9N Diamond is a full-ATX mainboard utilizing the standard 305 x 245mm size.  This mainboard does not offer a cooling solution on its voltage regulator transistors as other top-end mainboards have. 

On the mainboard you will find:

• CPU Socket AM2
• ATX 24-pin Power Connector
• 2 ATX 4-pin 12V Power Connectors
• NB Fan Power Connector
• SYS Fan Power Connector
• CPU Fan Power Connector
• PWR Fan Power Connector
• 2 PCI Express x16 Slots
• 2 PCI Express x1 Slots
• 2 PCI Slots
• CD-in Connector
• 2 Front Panel Audio Connector2
• 2 IEEE 1394 Connectors
• 3 USB 2.0 Connectors
• D-Bracket2 Connector
• Front Panel Connectors
• 6 SATA Connectors
• Clear CMOS button
• 1 ATA 133 Connector
• 1 Floppy Disk Drive Connector
• 4 DIMM Memory Slots
• Chassis Intrusion Switch Connector
• IrDA Infrared Module Header

On the rear panel you will find:

• 2 Gigabit Ethernet ports
• 1 Firewire port
• 4 USB 2.0 ports
• Analog audio input/outputs (7.1 format)
• SPDIF coaxial and optical outputs
• 1 serial port
• 1 parallel port
• PS/2 mouse connector
• PS/2 keyboard connector

Main power comes from a standard ATX12V v2.x (24-pin) connector.  The CPU is powered by its own 12V (JPW1) connector.  This motherboard also has an extra 12V power connector (JPWR2) using a regular peripheral power plug, although I am unsure what this is specifically used for.  The motherboard is compatible with older ATX 1.4 (20 pin) power supplies, just make sure you have enough power on the 12V line to support the mainboard.

Nvidia nForce 590 SLI chipset.  The MSI K9N Diamond uses the Nvidia nForce 590 SLI chipset which supports a total of 48 PCI Express bus lanes along with Quad SLI support. 

The nVidia 590 SLI chipset introduces a memory feature called the Enhanced Performance Profiles or EPP.  This is an open memory standard put forth by Corsair and nVIDIA which takes over where JEDEC's SPD left off.  As the Enhanced Performance Profiles description implies, it adds performance profiles to the memory SPD in addition to the conservative compatibility settings already programmed in.  EPP compliant memory is dubbed "SLI Ready" memory on nVidia platforms and allows the system to dynamically tighten up memory timings and increase voltages for better performance with no fuss.  Whether you're a novice or experienced computer user, the benefits of EPP are immediate.

When the nVIDIA nForce 590 SLI chipset is equipped with GeForce 7900GTX class or higher video cards, the chipset will automatically activate the nVidia LinkBoost technology.  LinkBoost increases the PCI Express x16 buses to the video card by 25%, and it also does the same for the HyperTransport link between the NorthBridge and SouthBridge chipsets.  While increasing the PCI Express bandwidth to a GeForce 7900GTX might be a bit redundant, future generation video cards will benefit from this available setting.  The 590 SLI is the only model that offers dual x16.  PCI_E1 is a full x16 when used in single card mode.

Finally nVIDIA has greatly upgraded its nTune software which allow users more control over their systems.  Realistically with nTune, there is no longer a need to go into the BIOS to adjust settings, now you can do everything within Windows.

AMI Bios.  American Megatrends, Inc. offers their great bios on the MSI K9N Diamond.  Main menu choices are:

• Standard CMOS Features
• Advanced BIOS Features
• Advanced Chipset Features
• Integrated Peripherals
• Power Management Features
• PNP/PCI Configurations
• H/W Monitor
• Cell Menu
• Load Fail-Safe Defaults
• Load Optimized Defaults
• BIOS Settings Password
• Save & Exit Setup
• Exit Without Saving

See my Bios page for specific bios settings.

RAID.  Nvidia RAID (0/1/0+1/5/JBOD) comes standard on the MSI K9N Diamond with the nForce 590 SLI chipset.  There are the two usual RAID configurations available:  Non-bootable and Bootable RAID Array.  The available RAID modes are:

• Mirroring (default)
• Striping
• RAID5
• Spanning
• Stripe Mirroring

The RAID drivers are included on the enclosed Drivers & Utilities CD.

Socket AM2.  The CPU bracket is very well placed and supports all Socket AM2 processors from the AMD Athlon 64/FX/X2/Sempron series.  The Socket AM2 AMD processor connects to the C51XE NorthBridge via a 1 GHz HyperTransport connection. 

MCP55PXE SouthBridge.  The SouthBridge chipset carries most of the load on the MSI K9N Diamond mainboard.  In pure form, the SouthBridge is able to handle up to 5 bus mastering PCI slots, the MSI K9N Diamond has one such slot, PCI 2, which is orange.  The MCP55PXE also supports one PCI Express x16 link, which means users get full video card bandwidth when running two nVIDIA video cards in SLI.  The MCP SouthBridge is able to support a PCI Express x8 link and six PCI Express x1 links.  The MSI K9N Diamond comes with the following PCI slots:

• 2 PCI Express x16 Slot
• 2 PCI Express x1 Slot
• 2 PCI Slots, supporting 3.3V/5V PCI Bus Interface

There is a direct link to the SouthBridge for the two Gigabit Ethernet connections, which include nVIDIA's DualNet technology.  The MCP55PXE SouthBridge's heatsink has a short copper heatpipe connecting it to the large heatsink on the C51XE NorthBridge chipset.  The size and low profile of the SouthBridge chipset does not interfere with the video card placement.

C51XE Northbridge.  The NorthBridge chipset is built on TSMC's 90nm manufacturing.  The nVIDIA nForce 590 SLI chipsets have a total of 46 PCI Express lanes available divided into 9 links.  The C51XE SPP NorthBridge supplies one PCI Express x16 link while the MCP55PXE SouthBridge handles the remainder of the PCI Express lanes.  The NorthBridge heatsink is made up of 26 aluminum fins and is cooled by a 40mm fan.

DDR2 DIMM.  The MSI K9N Diamond supports up to 8GB of dual-channel DDR2-800 memory.  The placement of the DIMM slots on the mainboard do not conflict with any other slots or ports, making this mainboard itself very nicely laid out.  The four DDR2 DIMM memory slots can handle 8GB of DDR2-800 unbuffered non-ECC RAM.  For dual channel mode you will have to used match memory pairs in each channel bank (DIMM 1+3 or DIMM 2+4).  DIMM sockets 1 and 2 are green and sockets 3 and 4 are orange.

Dual Gigabit LAN.  The MSI K9N Diamond comes equipped with two Vitesse VSC8601 Ethernet controllers.  The dual Gigabit network cards each have their own special connections to the MCP55PXE SouthBridge so bandwidth with the PCI bus isn't affected.  Users can combine the two connections for more bandwidth, and there is hardware TCP/IP Acceleration which lowers CPU utilization.  nVIDIA's FirstPacket Technology allows you to prioritize network traffic.  So for example, if you are a gamer that tends to do multiple things while you're online, you can prioritize your game traffic so that ping times are not affected by the other processes going on in the background.  Dual Gigabit LAN really is a great feature!

Creative Sound Blaster.  The integrated Sound Blaster CA0106-WATLF audio controller with Cirrus Logic CS4382 codec is one of the top highlights of the MSI K9N Diamond.  It offers 24-bit/96 KHz audio quality, 100db signal-to-noise ratio (SNR) – which is a professional level and up to 7.1 channel audio with SPDIF-out.  It also supports EAX Advanced HD 3.0 and Dolby Digital EX. 

Onboard audio connectors include the yellow SPDIF output next to the IEEE 1394 connector.  On the audio jacks, there's line in, line out, microphone, RS (rear surround) out, and CS (center, subwoofer) out connector.

SATA II.  The MSI K9N Diamond features six SATA II ports which are connected to the nForce 590 SLI MCP55PXE SouthBridge.  These are all 3GB/s SATA II ports.  The six SATA II ports are all neatly grouped together at the bottom right hand corner of the mainboard and they are color coded blue to help make the installation process easier.

IDE.  The mainboard supports a single IDE Ultra 133 channel enabling a Master and Slave device to be installed.

Floppy.  Supports up to two standard floppy drives.

Universal Serial Bus (USB).  There are four USB 2.0 jacks at the back of the MSI K9N Diamond.  On the mainboard proper there are three USB 2.0 headers for six additional jacks.  The included D-Bracket 2 acts as a Port 80 card to help diagnose problems during boot-up and may be very useful in case installation problems arise.

IEEE 1394 Firewire.  The MSI K9N Diamond nForce 590 SLI mainboard utilizes the VIA VT6306 chip to offer three IEEE1394 ports.  These have a transfer rate up to 400Mbps.  One port is located on the back panel and two pin headers are located on the mainboard.

Clear CMOS button.  On additional feature included on the MSI K9N Diamond is the Clear CMOS button (SW1).  If you ever have the need to clear CMOS all you have to do is power down the system and push the Clear CMOS button to clear the system configuration data.

Conclusion.  The MSI K9N Diamond mainboard is laid out nearly perfectly making this a very easy system to build.  Most of the connectors on the mainboard have been color coded to assist assembly and prevent errors.  The Nvidia nForce 590 SLI chipset is the top of the 500 Series line and makes this mainboard a top gaming machine.  The Socket AM2 is the current top-of-the-line AMD mainboard and is capable of holding several different CPUs.  What makes this board so strong is the SouthBridge and NorthBridge chipsets and their support for x16 PCI Express Link.  MSI really did a great job with their styling on the mainboard.  The Creative Sound Blaster audio controller is also a high selling point, not found very often on other mainboards.  This is a significant cost savings for those who want professional grade sound without having to pay for an additional sound card.  Another gamers dream is the dual-gigabit LAN which allows the user to prioritize network traffic.  As DIMM becomes so important in today's PCs the ability to add 8GB of DDR2 800 should surpass everybody's needs.  USB 2.0 and Firewire round out a great mainboard that should mark the MSI K9N Diamond as cutting-edge for a long time to come.  At its current selling price, it's a real steal that should be within reach of many buyers.  All-in-all a very impressive package from Micro Star International!