NVIDIA nForce5 500 Series
AMD aren't the only ones launching new goodies today. A socket shift can also be paired with new core logic, and NVIDIA have decided to unleash their latest nForce variant exclusively with Socket AM2 on the AMD side of the fence, launching the nForce5 500 series of SKUs at the same time as AMD release the socket and CPUs to go in them.We'll stick to the high-end enthusiast class variation of nForce5 -- nForce5 590 SLI -- for the time being, since it bundles all the nForce5 features and performance enhancements. There's also nForce5 570 SLI, 570 Ultra and 550 and we'll cover those in a separate piece in due course.
Like the AMD version of nForce4 SLI X16 before it, nForce5 590 SLI is a two-chip core logic set based on PCI Express and supporting NVIDIA SLI. The C51XE 'northbridge' IC connects to the CPU and provides the PCI Express interconnect for the first graphics board, and the MCP55 'southbridge' does the rest, including implementing another 28 lanes of PCI Express.
The pair of ICs further supply a new 6 port SATA2 controller with RAID, 10 USB 2.0 ports, HD Audio link for use with a HD Audio CODEC, new and improved ActiveArmor networking controller with dual GigE MACs and new features, SLI Memory/EPP, LinkBoost overclocking technology and more.
The spec first, then a look at each of the new features in turn.
Specification
| NVIDIA nForce5 590 SLI Specification | |
|---|---|
| CPU Support | All AMD Socket AM2 processors, SLI Memory |
| PCI Express | 26 lanes from MPC55, 20 from C51XE |
| Disk Controllers | 6-port SATA2 controller from MCP55, RAID0,1,0+1,5 |
| Ethernet Controllers | Dual GigE MACs, ActiveArmor, FirstPacket, DualNet from MCP55 |
| Audio Controller | HD Audio/Azalia link from MCP55 |
| Factory Overclocking | NVIDIA LinkBoost™ 25% link speed increase MCP<->C51 25% PCI Express graphics ports 25% HyperTransport<->CPU |
| Memory and Voltage Adjust | 0.775V to 2.200V Vcore 1.80V to 2.50V Vdimm 0.90V to 1.25V Vterm 1.20V to 1.45V IC Vcore 1.20V to 1.50V IC Vldt |
| USB controller | 10 USB 2.0 ports from MCP55 |
At the risk of repeating myself, it's a two-IC core logic set for AM2, based heavily on PCI Express, and the new things over the old AMD nForce4 SLI X16 include HD Audio from the southbridge (present on other nForce4 SKUs already), a pair of GigE MACs with all new features, new disk controller with 6 SATA2 ports and RAID5, and the juicy-looking factory overclocking.
It's not often you get to add factory overclocking to the list of core logic features a vendor supports across all of its board partners, but nForce5 590 SLI allows your author to do just that. NVIDIA screen the ICs used to make nForce5 sets and use the best for 590 SLI.
Let's talk about each feature in turn, including the factory clock adjust.
LinkBoost™
LinkBoost™ is where all the overclocking happens, an NVIDIA nForce5 590 SLI board upping the clocks well past reference to increase performance. Effectively all the major links get a 25% clock boost with LinkBoost™ enabled, including the CPU's HyperTransport<->C51XE link (itself 16-bit both ways), the PCI Express lanes driving the graphics hardware, and also the HyperTransport link between C51XE and MCP55.The PCI Express graphics link overclocking seemingly only happens with 7900 GTX for the time being, NVIDIA quietly locking it out from use with other 90nm G71-based SKUs like 7900 GT.
The important thing is that it's supported by NVIDIA, doesn't void any warranty and is guaranteed to work. It's been found that 7900 GTX overclocks best when the PCIe link its sitting on is driven higher (possibly some internal clock is driven by the PCIe reference clock), so the LinkBoost™ jump might enable even higher user-led graphics overclocks via the BIOS or software.
nForce5 590 SLI also defines a set of voltage ranges for system components that can be altered in real-time by software and the BIOS, in order to make LinkBoost™ work properly, should a voltage increase be needed to sustain the new clock level. That leads on nicely to SLI Memory.
SLI Memory
I list SLI Memory as a CPU feature, given the nature of the on-board memory controller. We published a quick intro to SLI Memory -- also known as EPP or Enhanced Performance Profiles -- here.EPP/SLI Memory exists to factory overclock your memory modules if they have support, on nForce5 590 SLI. The basic premise of EPP is that it hijacks part of the established SPD ROM area on memory modules in order to provide more comprehensive timing and voltage information to the core logic, which uses that information to set the best parameters on the CPU's memory controller.
It largely takes the hard work out of an overclock a user would most likely attempt themselves, running your memory modules at higher speeds (with the right timings and voltage) without the worry about stability.
However, it requires the support in the memory module for a correctly programmed EPP memory space inside the SPD ROM. Look out for the "SLI Ready" sticker and specification when you buy your module packs, and of course since it's a Socket AM2 core logic set it just applies to DDR2 memories. Want to see a pack of SLI Ready memory? Of course you do.
Note the SLI Ready sticker. That particular Corsair XMS2 8500 DDR2 is rated to DDR2-1066 and in an SLI Memory nForce5 590 SLI system it'll be run at around that speed, despite the memory controller on Athlon 64 FX and Athlon 64 X2 only officially supporting DDR2-800. That's what SLI Memory is all about, really.
It requires BIOS support on the nForce5 590 SLI board and the right memory modules, which then enable an SLI Memory on/off toggle in the board BIOS that you can set for faster memory speeds. In our testing on Foxconn's C51XEM2AA nForce 590 SLI mainboard, using the pictured modules, EPP ran the memories at 470MHz (940MHz DDR), 5-5-5-15-2T. More on that later.
Each module supplies at least 2 EPP profiles for the nForce5 590 SLI set to program the memory controller with, with modules possibly supporting 4 abbreviated profiles should the vendor choose to provide them.
It's not the first time a chipset has allowed overclocking past the official norm, indeed far from it, but it's definitely the first time it's been enabled with the help of the memory vendors to make it easy and warrantied. Even if no other core logic vendor chooses to support it, and even if JEDEC reject it when presented with the spec, EPP modules work just fine in non nForce5 mainboards, so you can't lose out by buying the modules.
Network and disk I/O features of nForce5 590 SLI deserve a fresh page, follow me.