Comparison of motherboards supporting the new memory standard PC2100 (DDR266)
AMD processors have long gained popularity among computer users due to their high performance at low cost. Therefore, it is understandable that new motherboards for AMD processors will appear on the market with support for the 133 MHz system bus frequency (the equivalent frequency is 266 MHz) and with DDR SDRAM PC2100 memory support. So far, only the AMD-760 chipset provides this capability.
AMD-760 is a new chipset developed by AMD engineers for its processors operating at a system bus frequency of 100/133 MHz. Unlike VIA chipsets, the new AMD chipset exchanges data between the processor and memory synchronously. Therefore, it is faster than VIA chipsets, all other things being equal.
The AMD-760 chipset includes two chips:
south bridge AMD-766.
The main highlight of the chipset is, of course, the north bridge.
The uniqueness of the AMD-761 Northbridge is to support a new type of DDR SDRAM: PC1600 and PC2100 DDR SDRAM. The numbers in the title show the theoretical maximum memory bandwidth: 1.6 GB / s on the PC1600 and 2.1 GB / s on the PC2100. Their difference is that the PC1600 memory operates at a clock frequency of 100 MHz, and the PC2100 – at a frequency of 133 MHz.
The DDR SDRAM memory transfers twice as much information per clock cycle as it does in SDRAM memory. Therefore, theoretically, DDR memory is twice as efficient as SDR memory operating at the same frequency. The north bridge allows you to install 7 PCI expansion slots on the motherboard and supports AGP 4x.
The AMD-766 south bridge is quite standard for today: it supports the ATA / 100 specification, four USB ports (two-channel USB controller), AC’97 / MC’97 interface. But to reduce the overall cost of the final product – the motherboard – manufacturers prefer to use VIA 686B, compatible for pinout with AMD-766.
It is clear that such high-performance boards cannot be widely distributed due to the small number of chipsets themselves. Still, AMD is no longer selling chipsets for sale, but as an example of how to do it. Nevertheless, such boards already exist.
In this review, we will share our impressions of two boards: GA-7DXC manufactured by Gigabyte and AD11 made by FIC. Both of these firms are well-respected as manufacturers of good motherboards, and we expected to enjoy the testing process in advance. That’s what we got.
Both boards are similar in their characteristics, like twin brothers.
Supported: Socket A Athlon 750 … 1200 MHz processors with 100/133 MHz FSB.
Socket A Duron 600 … 850 MHz processors with 100 MHz FSB.
AMD-761 Northbridge supporting AGP 4x and DDR SDRAM (PC1600 / 2100).
Southbridge VIA VT686B.
Two 2.5-volt 184-pin DDR DIMM slots supporting up to 1GB PC2100 DDR SDRAM.
AGP slot supporting 4x mode and Fast Writes.
5 PCI slots compliant with the PCI 2.2 specification.
Software AC’97 sound controller.
Input / output ports
One port for FDD, two serial and one parallel ports, ports for PS / 2 mouse and keyboard.
Sound linear input and output, microphone input, game port.
Two built-in USB ports.
Integrated UltraDMA / 100 IDE Controller
2 channels UltraDMA / 100 Bus Master IDE (with support for up to 4 ATAPI devices).
2-megabyte Flash EEPROM Award BIOS with ACPI support for Win98 / ME / Win2000, PnP, DMI and anti-virus functions.
Awakening from the modem, mouse, keyboard, network, USB devices and timer.
Suspend-To-RAM function support.
ATX form factor, 24.4 x 30.5 cm.
The only difference is that the CNR slot is installed on the FIC AD11 board, but it is not on the Gigabyte GA-7DXC board.