MSI X299 SLI Plus LGA 2066 Motherboard Review

Author:Daniel Dobrowolski

Editor:Kyle Bennett

Date: Tuesday , September 05, 2017

Intel’s latest chipset launch requires new motherboards. Everyone has entirely new product lines to look at so we kick things off with MSI’s X299 SLI Plus. This is a basic offering which we have tested with the Intel Core i9-7900X and Intel Core i7-7740X. Again MSI shows us how less is sometimes more.


MSI is one of the world's largest and most well-known motherboard manufacturers. In recent years, MSI has become a brand which is focused on PC gaming to the point of rebranding almost all its products and motherboards with "Gaming" branding. Most of these parts have a red and black color scheme and sport a dragon logo on them. MSI, like many other manufacturers has diversified its product portfolio in recent years to include graphics cards, laptops, and other computer related products.

MSI's X299 SLI Plus is a bit different as it isn't part of the gaming brand and lacks the gaming themes typical aesthetic. Given that the X299 Express chipset is intended for motherboards in the HEDT market, MSI's X299 SLI Plus needed to be more mature and not have a sole focus on gaming. It is part of MSI's Pro series and not the gaming series. It's black and white color scheme is far more conservative. It's not as colorful as many of MSI's other offerings. Not that MSI is a particularly bad offender in this area. The HEDT market is fickle and people build systems with 6, 8, or greater core CPUs for a wide variety of purposes. MSI's X299 SLI Plus looks like it would be as at home in a professional workstation as it would a gaming box and I like the elegant simplicity MSI is capable of sometimes. With the right CPU, there is support for 68 PCIe lanes, multi-GPU with either Crossfire or SLI. There are nine power phases with black, solid electrolytic capacitors and an external clock generator which allows a great deal of freedom in overclocking. MSI uses high quality components for its power phases which results in stability and longevity. At least in theory, which is something I will talk about in more detail later.

Main Specifications Overview:

Detailed Specifications Overview:


The packaging is standard issue in the industry. The box is basic black with relatively plain artwork. Inside the box there isn't a whole lot in the way of included extras. You get the driver disc, user manual, SATA cables, and an I/O shield. The motherboard is packed with a simple cardboard insert and an anti-static bag. This kept it damage free during shipping.

Board Layout

The layout of the X299 SLI Plus is good overall, but it does have a few issues for me to nitpick about. The main one being the location of the M.2 slot. It's right underneath the primary PCI-Express x16 slot where your graphics card would be. I'm not a fan of baking M.2 drives. What's interesting though, is that the X299 SLI Plus does have temperature monitoring of the M.2 slots, and it does have a shield with thermal tape on it. This may allow for a reasonable comparison of drives in and out of what would appear to be an easy bake oven for SSD's. The layout includes 6x 4-pin FAN headers which all support DC and PWM control modes. A 2A water pump header has also been provided.

With X299 comes the first completely new socket for the first time on the HEDT platform in many years. We've had various versions of LGA 2011 now with multiple compatibility barriers, but it remained pretty much the same mechanically. The new socket is an LGA 2066 type socket. MSI is using a modified version of it called the "Turbo Socket." The socket area is generally clear of major obstructions. The VRMs appear on only one side of the socket due to the amount of space that gets taken up by DIMM slots. There are nine power phases in all.

There are eight 288-pin DDR4 DIMM slots supporting up to 128GB of DDR4 DRAM at speeds of up to DDR4 4500MHz. It's interesting to note that MSI's specifications indicate dual channel CPUs support a slightly higher memory frequency than the quad channel capable models do. It shows 4133MHz for quad channel and DDR4 4500MHz for dual channel. Once again, MSI is bucking the trend and has gone with dual locking tabs on the DIMM slots. These slots aren't color coded to denote proper dual or quad-channel memory mode operation. While I understand this is nice looking aesthetically, I think the color coding would be nice here.

Intel's X299 Express chipset is located in the usual area. You will find it's covered with a low profile, passive heat sink which has some chrome backed slots in it. Those slots have LEDs around and are part of MSI's "Mystic Lighting" solution. The fit and finish of the heat sink is good and more importantly, it's screwed into place and feels solid. In front of the chipset you will find 8x SATA slots and 1x U.2 slot.

The expansion slot area is laid out well enough but it's not perfect. I don't care for the positioning of the M.2 slots as they are right under the graphics card slots. This ensures that your SSDs reside in a virtual Easy Bake Oven. In case being under a GPU wasn't enough, MSI has a shroud on the first 2280 type slot which is underneath the primary PCI-Express graphics card slot. The second supports type 22110 and smaller devices. It lacks the oven shroud, and is less likely to get used with SLIs fading popularity. Fortunately, the MSI X299 SLI Plus has M.2 temperature monitoring, which is nice.

The PCI-Express slots themselves are far more confusing. The X299 chipset itself offers 24 PCI-Express lanes while some CPUs only give you 16 lanes. The CPU installed here can greatly Impact the utility of the motherboard. With a 44x lane CPU, the X299 SLI Plus supports expansion slot configurations of x16/x16/x8 lanes. 28-lane CPUs support an x16/x8/x4 lane configuration. Using a 16-lane CPU nets you an x8/x4/x4 lane configuration. Why you would use one of those lesser CPUs on this platform is beyond me. Naturally with SLI in the motherboard's model name, Crossfire and SLI are supported.

The primary and secondary PCI-Express x16 slots use MSI's steel armor, which prevents sheering or PCB warping during card installation. The steel armor is also aesthetically pleasing, though I wish the third PCI-Express x16 slot received the steel armor treatment as well. There are also 2x PCI-Express x1 slots as well, and these are connected to the X299 Express chipset and not the CPU.

The I/O shield area is packed with connections. You will find a clear CMOS switch, a BIOS flashback + button, 1x PS/2 keyboard or mouse port, 1x BIOS flashback port, 4x USB 2.0 ports, 4x USB 3.1 Gen1 ports, 2x RJ-45 LAN ports, 1x USB 3.1 Gen2 Type-A port, 1x USB 3.1 Gen2 Type-C port, 5x 3.5mm stereo jacks, and 1x optical S/PDIF out connector. The audio jacks are gold plated and use color coded trim rings to aid in connecting your devices to the correct ports. USB 2.0 ports are the standard black, while USB 3.1 ports are standard "teal" color.