nForce4 SLI Roundup: Painful and Rewarding

Gigabyte K8NXP-SLI: Features and Layout

Specification	Gigabyte K8NXP-SLI
CPU Interface	Socket 939 Athlon 64
Chipset	nForce4 SLI (single chip)
BUS Speeds	200MHz to 400MHz (in 1MHz increments)
PCI/AGP Speeds	Asynchronous (Fixed)
PCI Speeds	100MHz to 150MHz in 1MHz increments
Core Voltage	Auto, 0.80V to 1.75V in 0.025V increments
DRAM Voltage	Normal, +0.1V, +0.2V
Chipset Voltage	Normal, +0.1V, +0.2V, +0.3V
Hyper Transport Ratios	Auto, 1x to 5x in 1x increments
LDT Bus Transfer	16/16, 16/8, 8/16, 8/8
LDT Voltage	Normal, +0.1V, +0.2V, +0.3V
CPU Ratios	Auto, 4x to 25x in 0.5x increments
Cool'n'Quiet MAX FID	Auto, 8.0 to 13.0 in 0.5x increments
DRAM Speeds	Auto, 100, 133, 166, 200
Memory Command Rate	Auto, 1T, 2T
Memory Slots	Four 184-pin DDR Dual-Channel Slots Unbuffered Memory to 4GB Total
Expansion Slots	2 x16 PCIe Slots 2 x1 PCIe 2 PCI Slots
SLI Setup	Movable PCB Card
Onboard SATA	4-Drive SATA 2 by nF4 PLUS 4-Drive SATA by Sil3114
Onboard IDE	Two Standard nVidia ATA133/100/66 (4 drives)
SATA/IDE RAID	4-Drive SATA 2 PLUS 4-Drive IDE (8 total) Can be combined in RAID 0, 1 PLUS 4-Drive SATA by Sil3114 Sil3114 Raid 0, 1, 5
Onboard USB 2.0/IEEE-1394	10 USB 2.0 ports supported nF4 3 1394B FireWire 800 ports by TI chip
Onboard LAN	Dual Gigabit Ethernet PCIe by Vitesse VSC8201 PHY PCIe by Marvel 88E8053
Onboard Audio	Realtek ALC850 8-Channel codec with 6 UAJ audio jacks, CD-in, front audio, and coaxial SPDIF In and Out
Other Features	Gigabyte Dual BIOS
BIOS	Award 2/01/2005

The shipping Gigabyte BIOS for the K8NXP-9/K8NXP-SLI family provides a wide and useful range of adjustments for many features, with the notable exception of a very limited range of memory voltage adjustments compared to other boards in the SLI roundup. As is the Gigabyte custom in recent designs, Advanced Chipset Features (and Memory Timings) can only be seen when you hot press CTRL+F1 while in the BIOS. HyperTransport adjustments are also provided in the hidden Advanced Chipset Features menu.

There are no BIOS options for adjusting or controlling SLI. This is handled in the nForce4 platform drivers and the nVidia graphics drivers.

The Gigabyte K8NXP-SLI, like the sister K8NXP-9, was designed as a top-of-the-line nForce4 motherboard. As the flagship model, it sports all the top Gigabyte features.

The SLI version features start with the trademark DPS daughter card that you can see on the right of the board picture. This is used to increase power reserves and stability by increasing the board to 6-phase power. You can see the DSP slot to the left of the CPU, and the trademark Gigabyte dual BIOS chips to the right of CPU. This Gigabyte feature provides back-up BIOS in the event of a bad flash or unstable BIOS setting.

Gigabyte provides eight SATA ports. Four ports are 3Gb/s ports provided by the nForce4 chip, and the four additional are the 1.5Gb/s ports driven by the Silicon Image 3114. The 2nd group of ports is useful, but they would have been much more exciting if they had been 3Gb/s ports like those provided by nForce4. They do support Raid 5.

We are pleased that Gigabyte uses the nF4 on-chip Gigabit LAN by supporting it with a Vitesse (Cicada) Gigabit PHY. Gigabyte then goes one step further by including a second Gigabit LAN on the PCI Express Bus. This second LAN is also removed from the constraints of the slower PCI bus as it resides on the much faster PCIe bus.

Audio is AC '97 2.3, supported by the popular 8-channel Realtek ALC850. The K8NXP-SLI9 includes a wide range of audio I/O provided to make the most of the 850 chip. This includes 6 programmable audio mini-jacks and coax SPDIF in and out - all on the rear panel.

A pioneering feature for Gigabyte has been their support of high-speed 1394B Firewire on their boards. This continues with the K8NXP-SLI with 2 ports capable of 800MB/s or Firewire 800. This is double the speed of 1394A for those looking for fast Firewire access.

From a feature, board layout, and BIOS options point of view, the K8NXP-SLI can be considered the twin of the K8NXP-9. The only real change is the replacement of one PCI slot with a second PCIe video slot. All the good things about the features and layout of the K8NXP-9 are still here in the K8NXP-SLI.