The newest high-end PCs run into some trouble
Senior associate editor
Updated February 9, 2006
When we heard about AMD's new dual-core Athlon 64 FX-60 CPU, we were excited to get our hands on both the chip and the high-end gaming systems we knew would feature it. We were shocked, though, when we started testing these hot new PCs and found that two of the best-looking of the bunch couldn't play Doom 3 at its highest settings. The Velocity Micro Raptor 64 DualX is a $5,500 system. The Falcon Northwest Mach V costs $6,500. At those prices, anything less than perfection is unacceptable.
"It's the overclocking!" screamed AMD. "It's the graphics drivers!" yelled one system vendor. "It's your power outlets!" bellowed another. (Another vendor pleading the same case, whose system dropped out entirely, quizzed us on Ohm's law.)
Balance of power
Turns out it was none of those things. With the cooperation of all involved, we narrowed down the issue to the power supplies. What's actually happening is still under investigation, but the broad view seems to be that, despite the 600-watt PSUs in each system, the power demands of all the parts, most particularly the pair of overclocked 512MB GeForce 7800 GTX 3D cards in each, is too much for the system during the most demanding gaming scenarios. Adding more raw wattage will solve the problem, as Velocity proved with the introduction of its new 1-kilowatt power supply. Falcon Northwest CEO Kelt Reeves said he solved the problem by adding even more hard drives to a comparable system, a solution that, while counterintuitive, indicates a power balancing problem.
Regardless of what's going on, we were most shocked that the power supplies are the source of the glitch, because both models (a SilverStone Strider ST60F in the Falcon, an EnerMax 701 in the Velocity) passed Nvidia's SLI Certification, which means that they should work. Nvidia's official response is as follows:
"We are investigating the power draw of the high-end SLI PC designs brought to our attention by CNET. For standard SLI PCs using our GeForce 7800 GTX or 7800 GTX 512MB boards, we currently recommend SLI-Ready certified power supplies, all with at least 500W power output and 30 amps on the +12V rails. Power supplies with even higher power output are likely required in SLI PCs with many devices and/or overclocking of CPUs and GPUs. SLI-Ready certified power supplies are certified when powering nonoverclocked systems."
To keep things in perspective, though, the Falcon set records on several benchmarks, and the Velocity offers a relative bargain for such a high-end PC. We suggest you give the vendors a call when ordering to get help configuring the most stable configuration. Hopefully, by then, Nvidia and the power supply vendors will have worked out the kinks.