The gateway between a processor and other components is a set of interface controllers generically called the chipset. Traditional chipsets include a northbridge with memory controller and graphics card interface, and a southbridge containing slower expansion card interfaces and various peripheral, storage, and communications controllers. The closest match to this traditional definition, AMD’s Socket AM3+ deviates mostly in that the memory controller is on the CPU.
AMD and Intel also integrate a graphics controller onto their mainstream and low-cost processors, using the system memory controller to boost performance. These solutions are typically adequate for anyone who doesn’t play 3D games on their PC, and both companies occasionally surprise us with playable 1080p game performance.
AMD AM3+ Chipsets (by northbridge)
AMD’s 800-series chipsets provide a multitude of options for both discrete (no graphics) and integrated graphics customers. Northbridge products include:
- 990FX: with 42 PCI Express 2.0 lanes, this is the best match for multiple graphics cards. Unchanged from the 890FX, AMD renamed its core logic when revising its AM3 socket to AM3+. 990FX supports AMD’s CrossFire with up to four cards, and Nvidia unblocked this chipset to allow three-way SLI support as well.
- 990X: a lower-cost 26-lane version of the 990FX that supports a single graphics card with sixteen lanes or two cards with eight lanes per card. CrossFire is supported across two cards, and Nvidia allows for two-way SLI as well.
- 890GX: an integrated-graphics version of the 990X/890X that supports discrete graphics, integrated DirectX 10.1 graphics, and combinations of AMD discrete cards with integrated graphics. Because this chipset was launched before Socket AM3+, buyers must verify that the motherboard they’re considering is AM3+-compliant.
- 880G: a lower-cost version of the 890GX that supports a single AMD graphics card and integrated graphics simultaneously for enhanced multi-monitor support. It can also switch between discrete graphics and integrated engines to save energy.
- 970: a version of the 880G that has no integrated graphics and supports a single graphics card in true x16 mode. An additional graphics card can be hosted at reduced bandwidth by using four of the chipset’s x1 pathways.
AMD FM2+ Chipsets
One of the most amazing things about AMD’s mid-market APUs is that all three chipset generations support the newest-generation processors. This could lead to some confusion over which A55 motherboard comes armed with Socket FM1, FM2, or FM2+, so buyers need to pay close attention to specifications.
- A88X supports four PCIe 2.0 lanes in addition to the 20 hosted on the APU (a CPU with certain graphics capabilities built-in), four USB 3.0, ten USB 2.0, and eight SATA 6Gb/s ports. Unlike its competitor’s product, AMD also supports legacy PCI (up to three slots) in addition to newer interfaces. Launched in conjunction with the FM2+ socket, it appears to be a new stepping of the A85X with added USB 3.0 debugging.
- A78 represents a reduced feature set of the A88X, with six SATA 6Gb/s ports and the CPU’s ability to split its integrated PCIe controller from x16-x4 to x8-x8-x4 disabled. Like the above rebrand, the A78 is a new stepping of the A75 that coincides with AMD’s switch from Socket FM2 to Socket FM2+, again adding USB 3.0 debugging.
- A58 represents a reduced feature set of the A78, with six slower SATA 3Gb/s ports and no USB 3.0. Rebranded from A55, this part is unique in that it was launched after manufacturers started production of A55-branded Socket FM2+ motherboards.
- A55 was the original version of the A58, and is still available. Though we’re accustomed to rebranding, a change in the engineering codename from Hudson D2 to Bolton D2 seems disingenuous.
Intel LGA 1150 Chipsets
Because all northbridge functions have been moved onto LGA 1150-based processors, compatible motherboards feature only a southbridge that Intel relabels the PCH, for platform controller hub.
- Z97 Express features eight PCIe 2.0 lanes, six USB 3.0 ports, and six SATA 6Gb/s ports. Physically unchanged from the previous Z87 Express, Intel renamed it for its Haswell refresh marketing blitz, and changed the base firmware just enough to call it a new product. The altered firmware may be required for future Broadwell CPU support.
- Z87 Express: Intel enables pathway splitting for the CPU’s PCIe 3.0 controller when paired with Z97/Z87 Express, so that any processor can support a single card with 16 lanes, two cards with eight lanes, or three cards at x8-x4-x4 (depending on motherboard layout). CrossFire is enabled across as many as three cards, while Nvidia's SLI technology only works with two cards. RAID modes 0, 1, 5, and 10 are also enabled.
- H97 Express replaces H87 in the same way that Z97 replaced Z87. Both units currently support the same processors and feature set, but the newer chipset’s altered base firmware may be required for future Broadwell CPU upgrades.
- H87 Express reduces features compared to Z97 by limiting the CPU’s integrated PCIe 3.0 controller to a single device (one slot), and officially blocks CPU overclocking. Unofficially, the H97/H87 Express chipset can be unlocked for overclocking. Additionally, Intel enables its Small Business Advantage software on H97 or H87 motherboards with compatible firmware.
- Q87 Express adds a few more business-oriented features (VT-d, TXT, vPro) to the feature set of the H87.
- Q85 Express removes two SATA ports from the feature set of H87 Express, along with RAID functionality. The total number of supported SATA 6Gb/s ports is four.
- B85 Express removes four USB 2.0 and two USB 3.0 ports compared to Q85 Express. The total number of USB 2.0 and 3.0 ports is eight and four, respectively.
- H81 Express removes two additional SATA and two additional USB 3.0 ports compared to B85 Express. It also closes off two PCIe 2.0 lanes, leaving a total of six from the PCH-based controller. The least-expensive of Intel’s LGA 1150 products, it was proof-of-concept for our overclock-unlocking article.
Intel LGA 2011-v3
Recently replacing the X79 Express in LGA 2011 motherboards, X99 Express is the only desktop chipset for Intel’s DDR4-supporting LGA 2011-v3 (Haswell-E) processors. X99 capitalizes on the X79's "missing" features with ten SATA 6Gb/s ports, adds six USB 3.0, and retains its eight PCIe 2.0 pathways to support low-bandwidth devices. Relying upon Intel's 5900-series Core i7 processors (currently the Core i7-5960X and 5930K) to deliver up to 40 PCIe 3.0 lanes directly from the CPU to up to five slots, the platform drops to 28 PCIe lanes when paired with a 5800-series (Core i7-5820K) processor.
Though the most common configurations for this platform will use one or two high-bandwidth cards (Graphics, RAID or both), those who wish to build it with three or more cards and a Core i7-5820K should thoroughly read our reviews to understand its effect on each motherboards slot configuration. Certain models even lose 3-way SLI capability when using the Core i7-5820K.
Intel LGA 2011
Though end-of-life, value-seeking buyers who want a lot of PCIe connectivity may chose to pair Intel's earlier high-end platform with one of the firm's least-expensive LGA 2011 processors. The associated X79 Express chipset had only two SATA 6 Gb/s ports in addition to four SATA 3 Gb/s ports, though some motherboard manufacturers decided to expose the platform's four hidden SAS ports as SATA. This legacy product also lacked USB 3.0, though most motherboard manufacturers added a third-party USB 3.0 controller to one of the chipset's slow PCIe 2.0 pathways.