Intel's B660 chipset represents the affordable end of the Alder Lake platform, providing a modest home for the powerful 12th generation Core processors. At least, more modest than the impossibly expensive Z690 motherboard. However, there is an odd crossover point at the bottom end of the Z690, where more affordable motherboards like this $180 MSI MAG B660M Mortar WiFi DDR4 compete on price.

In most cases, however, the lower-priced Z690 boards are inferior to mid-priced B660s like this petite MSI slab in terms of overall feature set. But what are the real differences between the Z690 chipset and the B660 chipset?

Indeed, the only thing that is completely missed is the overclocking of the processor, while the rest is basically the same. So the 4-lane DMI interface is narrower and there are only 14 PCIe lanes from the chipset. It also has a smaller PCIe port configuration and fewer accessible USB ports compared to the Z690.

However, with full PCIe 4.0 support available, modern SSDs can run faster on mainstream chipsets and may even support PCIe 5.0 from Alder Lake CPUs if Mobo manufacturers choose to implement it.

However, MSI has not chosen to include such a luxury item on its B660 boards. But that is exactly what luxuries are: graphics cards that truly take advantage of the bandwidth offered by PCIe 5.0 will not appear for a long time, especially at the mainstream level, and Gen5 SSDs will also be very high-end products when they appear this year.

Everything you would want in a robust mainstream gaming PC is there: a full enhanced x16 PCIe 4.0 slot for the GPU, another full slot running at x4, and a final short x1 PCIe 3.0 slot. Few overclockers will miss this slot, and few will install multiple M.2 SSDs. Having two PCIe 4.0 M.2 slots for drives (one from the chipset and one from the Alder Lake CPU) should be enough for most users. [However, if MSI included BCLK overclocking support on the B660M, which is paired with some Asus and ASRock motherboards, more users might choose the B660M. stabilizing a Core i5 12400 at an all-core 5.2GHz is been my technical highlight of the year. Sadly, there is no support for the B660M Mortar, but it is likely to be removed from other manufacturers' motherboard BIOS releases as well.

When it comes to choosing a system memory setup as one of the more affordable routes to the Alder Lake platform, it makes sense to go the DDR4 route. There is also a DDR5 version of this motherboard, but it costs an additional £30 in the UK and you have to deal with the additional cost and scarcity of DDR5 modules.

Also, there are limited benefits to adopting the new technology when it comes to PC gaming performance. Since we could not find a listing for the DDR5 version in the U.S., MSI may well have thought twice about bringing it to the public.

After all, it is unnecessary at this price point. I believe we are trying to create an affordable gaming PC, and I think MSI has done a good job of that.

And MSI's MAG B660M is a great base on which to build it; the Mortar has eight USB ports on the back panel (including one USB 3.2 Gen2 Type-C) and numerous internal headers on the board itself, providing effective USB gaming . It also includes Realtek 2.5Gbps networking and Intel WiFi 6. The higher-end Z690 board has 10Gbps LAN and WiFi 6E, but for our purposes, this is another luxury item that can be ignored.

Gaming Performance

System Performance

As for performance, switching from DDR4 to DDR5 makes no significant difference at all: the 14-phase power design is configured so that the Vcore itself has 12 phases, and the 60A stages, combined with the MAG B660M can keep a normally clocked Core i9 12900K running at the same level as a much higher-spec Z690 motherboard.

However, the B660 boards we've tested so far have seen reduced gaming performance, so a mainstream chipset would not be the perfect choice for a gaming PC if one is trying to maximize the performance of its components. However, it must be said that the difference is still marginal and only really noticeable with super high-end GPU and CPU combinations, and even then only at 1080p.

When the GPU is constrained, as in lower-spec builds like the combination of a Core i5 12400 and a GeForce RTX 3050, the difference is negligibly small. However, if you are going to put an RTX 3080 or RX 6800 XT on the board, saving pennies on a B660 motherboard is not necessarily recommended.

The MSI MAG B660M Mortar WiFi DDR4 is a high-quality small micro-ATX motherboard, and being able to run an i9 12900K at stock settings on a board under $200 is impressive. The ability to run the i9 12900K in stock configuration on a board under $200 is impressive. This is an ideal board for building an affordable small form factor gaming PC, the only problem being that there are several DDR4-based Z690s in this price range that are a bit more affordable. However, it must be said that such products are few and far between. But otherwise, the MAG B660M offers performance, a basic feature set, and a beautiful two-tone appearance.