ASUS K7M AMD 750/VIA 686A Slot-A ATXby Anand Lal Shimpi on February 1, 2000 2:59 AM EST
- Posted in
What good is a fast processor if there are no reliable motherboards to run it on?
That was the question we asked ourselves when the Athlon originally held its debut back in August 1999. Luckily we didn't have to worry too much about answering that question because in virtually no time at all, there were reports of ASUS demoing their Athlon motherboard known as the K7M.
As a company, ASUS is up there in the ranks of AOpen, Supermicro, and Tyan in terms of their dedication to producing high quality motherboards. As a motherboard manufacturer, ASUS' products have always ranked among the highest in stability, reliability and performance. A trio of praise that most motherboard manufacturers can only dream of achieving, and something that ASUS is very well known for in the industry.
So it wasn't a surprise that ASUS' K7M was a very highly anticipated Athlon motherboard, but what definitely is a surprise is that until very recently, ASUS hadn't truly promoted the K7M as part of their extensive line of motherboards. Rumors and accusations began to arise of Intel pressuring Athlon motherboard manufacturers to refrain from promoting their Athlon motherboard solutions and ironically enough, there wasn't a single mention of the K7M on ASUS' website at the release of the motherboard.
As if that weren't enough, the K7M shipped in an OEM box with the ASUS name mentioned very few times in the manual itself. It was almost as if ASUS didn't want to associate themselves with the K7M but they did want to produce it and naturally enjoy the profits from what would eventually grow to be one of the most demanded motherboards from the Athlon community.
We have seen a major change in this policy of denial from ASUS as the K7M as well as its micro-ATX counterpart, the K7M-RM both now carry full product description profiles on ASUS' website both of which are publicity accessible from the front page of the web site.
Now that all of the political discussion is out of the way, it is time to take a look at the K7M as a motherboard solution for the Athlon platform.
New Anand Tech Report Card Rating 92/A
AMD 751 North Bridge
VIA 686A South Bridge
90 / 95 / 100 - 125 (in 1MHz increments)
133 / 140 / 150
1.30v - 2.05v (in 0.05v increments)
3 168-pin DIMM Slots
1 AMR Slot
1 AGP Slot
5 PCI Slots (5 Full Length)
1 ISA Slot (1 Shared / 1 Full Length)
Analog Devices 1881
The K7M, like the FIC SD11, was one of the first Athlon motherboards not to use AMD's 756 South Bridge. The original reasoning behind moving from AMD's 756 South Bridge, which was a perfectly able chipset as it supported Ultra ATA 66 and 5 Bus Mastering PCI slots, was in order to prevent from placing AMD in the position of being a chipset and a CPU manufacturer at the same time. While AMD's focus has slightly changed in recent times from not wanting anything to do with chipsets to more of a "we'll develop chipsets for every major jump in technology" stance, the fact of the matter remains that at the time the best move for ASUS was to implement VIA's 686A as the South Bridge on the K7M. This move actually didn't help them too much in the long run as marketing pressure from Intel seemed to be much worse on those companies that implemented VIA based solutions than on those that simply used AMD chipsets.
The VIA 686A South Bridge is what allows for the 5 PCI slots and the single ISA slot on the K7M as well as the Ultra ATA 66 support. The ISA slot is shared with the 5th PCI slot and is actually an OEM option as is having a second ISA slot which is an option that wasn't present on our evaluation sample. For the most part, if you purchase a K7M it will feature a 5/1/1/1 expansion slot configuration (PCI/ISA/AMR/AGP) but if you happen to find the K7M in an OEM system don't be surprised if you see an extra ISA slot or none at all.
The AGP slot on the K7M is a standard 3.3v AGP 2X slot, while the AMD 751 North Bridge used on the K7M does not support AGP 4X, from our testing the performance increase provided for by AGP 4X over AGP 2X is negligible and there isn't a single AGP 4X graphics card available on the market today that doesn't work in an AGP 2X slot.
Finally, the AMR slot on the K7M is provided for courtesy of the Analog Devices' 1881 Soundport Codec as is the onboard audio. Through the use of a relatively inexpensive AMR card, OEMs and system integrators can extend the AD1881's capabilities to provide for a soft modem connection as well. Keep in mind that the onboard audio as well as any AMR add-on devices that are used with the K7M will be driven by your CPU, so hardcore gamers and other such users may want to stick to their hardware PCI sound and hardware modem devices.
Then again, with the Athlon 500 being the slowest CPU you can purchase for the K7M, having a software based sound codec won't do too much damage in terms of overall performance. Of course if you'd rather use your own sound card, the onboard codec can be disabled through the board's BIOS setup or via a jumper block located above the third PCI slot.