How to Choose a Chipset from AMD (770, and 780G) for the Phenom CPU Family

By AMD: 770 and 780G

With Phenom CPU’s topping out at price and performance points well below Intel offerings, it is a fair assumption that most people building an AMD powered system will be choosing mainstream components. So AMD had better get these chipsets right.

The first hurdle they ran headlong into is their ancient southbridge. The SB600 has been around for so long that it has no place on store shelves… let alone your new computer. This little fossil has support for 4 SATA devices and 10 USB devices versus competitor offerings with 6 and 12 respectively. Furthermore, running Vista on it either requires that you run your SATA devices in IDE mode with the accompanying performance, or go through the lengthy and complicated fix Microsoft documents here. Even if you do all that, SATA performance isn’t where it should be.

It’s not that AMD is unaware of the problem; boards with a far more competitive SB700 southbridge were supposed to be out as of January 2008, with SB750 in the higher-end boards on their heels. Delay led to delay, and it is still hard to find these boards today. In summary, don’t touch an AMD chipset unless it has a SB700 or more recent southbridge.

AMD’s Excellent Integrated Graphics

AMD has done some very interesting things with their newer chipsets, particularly in terms of integrated graphics: the 780G and V come with HD 3200 and HD 3100 on board, respectively, the V model being intended for business use and eliminating some of the fancier video connection options. These graphics chips are modified from the RV610 that powers the Radeon HD2400 series. Though not the newest or highest end Radeon product, including the chip from a discrete GPU, as an integrated graphics solution it is changing the way people think about integrated graphics. Though not suitable for truly demanding graphics users, it brings a level of eye-candy that people who do without graphics cards have never seen.

The 780G is also a superbly efficient chipset, with very modest power and cooling requirements. All those graphics right on board, the low power draw, and availability in μATX make this an unparalleled choice for a home theater or Mini-PC (provided of course the model you’re considering has an SB700). The 770 with SB700 could be used successfully for a budget PC. It is also worth noting that AMD offers PCI-E 2.0 on all 7 series chipsets.

Before going this route though, be aware that many 770 and 780 based boards don’t support AMD’s fastest CPUs, the power hungry ones with Thermal Design Power requirements of 125w or more, such as the Phenom 9850. Some do, but research the issue very carefully for your specific board. AMD seems content with the argument that people who want to run their fastest processor will be happy to spring for a 790F or FX, even though the price difference on the boards is as much or greater than that of the CPU’s. Use AMD’s configuration tool to make sure your board/chip combo will run well, but it doesn’t look like they update it very often.

By nVidia (710a, 720a, 730a, 750a SLI, GeForce 8 series)

nVidia also takes major steps forward in terms of on board graphics. Their GeForce 8×00 boards, the only ones available from nVidia in µATX, have adopted a similar solution to AMD’s, and shoehorn the GPU from a GeForce 8400 on to the board. Like AMD’s 780G, nVidia has introduced Hybrid multi-GPU support, allowing an 8400 GS or 8500 GT to run in SLI mode with the onboard graphics. These chipsets all offer 6 SATA and 12 USB connections as well as PCI-E 2 support, as do the seven series of boards discussed below. Note that there are similar issues when trying to run a 125w CPU on an entry or mid-level nVidia based board as there are with AMD based boards.

The most recent 8300 version has graphics comparable to, but not quite as good as, the 780G, and the 780G consumes far less power as well, keeping it in the lead for the Mini-PC and HTPC builder.

Nvidia’s Hybrid SLI

nVidia is trying to do something about its (somewhat ironic) reputation for designing the least "green" chipsets out there though. Hybrid SLI includes two features, the aforementioned support for coupling a GPU card with the on board GPU in SLI, which they call GeForce Boost, and a system that uses the integrated GPU and shuts down graphics cards when they aren’t needed for 3D applications. This isn’t just saving some small amount of power to make you feel good about yourself; with top end cards sucking over 200 watts, and people running them two or three at a time, there should be an actual difference on your hydro bill from this technology, which nVidia calls HybridPower. Currently it seems a little spotty in use, with settings to turn the cards on and off by themselves as needed, not working as intended, but doing it manually from the desktop takes seconds and works fine. Hopefully a later BIOS will solve the automation question. In order to offer the power saving features to the multi-GPU enthusiasts who need them, all of nVidia’s seven series chipsets for AMD (save the bare bones 710a) have integrated graphics, including the flagship 780a SLI, and are discussed along with the enthusiast chipsets in the next article.

Sticking to the mainstream, the 710a has no on board graphics and thusly none of the Hybrid SLI benefits. It does, however, support 6 SATA and 12 USB connections. Stepping up to the 720a (available for under $100) gets you integrated graphics and Hybrid SLI. The 730a makes the graphics able to play HD 1080p. The 750a SLI adds, as one would expect, SLI support (SLI as in two cards, not the Hybrid SLI we’ve been discussing, but it has that as well in order to shut down the cards when not in use) by way of 2 x8 PCI-E 2 slots. People using one card will be able to set up boards to have x16 on the first slot. The 750a boards were also the lowest on the nVidia totem-pole to claim 125w support, with prices starting at $120.

Though the 780G is still king of the hill for a small, quiet box with HD video, the breadth and functionality of nVidia’s offerings beat out AMD’s for other types of mainstream build. The next article deals with enthusiast options for AMD CPUs.

Further articles in this series:

>>> Introduction

>>> Mainstream Chipset for Intel CPU’s

>>> Enthusiast Chipset for Intel CPU’s

>>> Mainstream Chipset for AMD CPU’s

>>> Ethusiast Chipset for AMD CPU’s

>>> Summary & Conclusion