Utilizing Lucid's Hydra 200 Silicon

Utilizing Lucid's Hydra 200 Silicon

It's time to check a thing or two out about the Hydra 200 chip used on this motherboard. Lucid's Hydra chip has been a topic of interest for many of us for a long time now and MSI Big Bang Fuzion offers the first real consumer implementation of that chip.

Can Lucid really design a chip that allows GPU load-balancing that works as smoothly as SLI and CrossFire and then allow mixing GPUs of different types? It's a daunting task for any company and over the time we got to spend with the Big Bang Fuzion, one thing became abundantly clear, it's not at all as easy as Lucid would like to make us believe. First let's have a quick chat about the technology.

The Lucid Hydra 200 chip functions as a load balancer in between two (and in the future three) GPUs. Load balancing requires some sort of computational power, and as such the Hyrda chip includes a RISC core (300MHz if I am correct) based on the Tensilica Diamond architecture. That core comes with with 64K of instruction memory and 32K of data memory, both on-chip. We learned that there are three versions of the Hydra 200 available. The only real difference between the chips are the number of PCIe lanes.

As such the low-end chip has just one x8 connection to the CPU/PCIe controller and two x8 connections to GPUs. Then the midrange LT22102 has a x16 connection to the CPU and two x16 connections for GPUs. And the highest end solution, the one being used on the MSI board, has a x16 to the CPU and then a configurable pair of x16s to GPUs. Configurable in the sense that you can operate this controller in 4 x8 mode, 1 x16 + 2 x8 or 2 x16.

The chip itself is outsourced and manufactured by TSMC on a 65-nm fabrication node, Lucid's Hydra 200 power draw is humble at a rated 6W TDP.

After both graphics cards (whether that is ATI or NVIDIA or a combo of them) have been seated you'll need to install the Hydra software driver. This driver suite will takeover and activate the Hydra 200 chip, which will now function as load balancer in-between the two cards, allowing them to (currently) run a small selection DX9 and DX10 games.

Hydra 200 accomplishes this task by catching calls from the graphics API (DirectX), vigorously dividing up the workload, and then assigning a portion of the work required to draw each frame to one of the GPUs. The Hydra 200 chip will then combine the data into an end-result sending it off to to the display.

Lucid Hydra can work in Three modes/configurations:

• X-Mode: A Radeon 4000 or newer and GeForce series G90/G200 graphics card
• N mode: Two GeForce series G90/G200 graphics cards
• R mode: Two Radeon 4000 or newer graphics cards

The biggest downside of the Hydra 200 chip is that it will require game profiles and driver optimizations to allow the games to work. As such there are restrictions, a whole lot of them really:

• Current supported cards: Radeon Series 4000/5000
• Current Supported cards: GeForce 9000 and GTX 200 series
• Only Catalyst drivers 9.7 and upwards supported
• Limited NVIDIA ForceWare support: 191.07 was the latest driver supported
• Very important - mixing NVIDIA and ATI GPUs will require Windows 7 -- Vista will not work.
• You need at least Windows Vista in order to create a single vendor Multi-GPU setup (Radeon/Radeon).
• Hydra will NOT work with cards that have two GPUs (Radeon X2 / GeForce GTX 295 etc).

So we see a lot of vendor dependency in order to get independent Multi-GPU vendor support.

Next to that there is, as we mentioned, driver profiles. Now I know the Lucid team is working hard on driver support, currently however the one mode everybody is after is the X-Mode (two vendor cards) and these are the only titles supported:

X-Mode (dual mixture of NVIDIA and ATI graphic cards)

• 3DMark Vantage
• 3DMark06
• Batman Arkham Asylum (including benchmark)
• Call of Duty 4
• Call of Duty World At War
• F.E.A.R. 2 Project Origin
• Operation Flashpoint Dragon Rising

In N or R mode things are way better supported though. These games are verified with HYDRA driver 1.3.105 by Lucid. The games that are highlighted (Bold) are common to all configurations.