I posted, its a Furmark issue, the same one that loaded the VRM's on the 4870 to the point of crashing.
The lightning has extra and higher capacity VRM's, they are for overhead, cooler running and removing a bottleneck from overclocking. But that overhead is eaten into by furmark, while real gaming will not use that extra power.
Furmark is odd, as people have called it its almost a power virus, somehow it loads the VRM's fully, even if that extra load offers no performance, no idea how it does it.
In a real gaming situation the 480/5870 stock cards would likely drop in load by a similar amount, the 5870 lightning will likely drop a stupid amount, basically ending up in line with an overclocked 5870 usage.
Other than that, rather pointless card, ok others might get more out of it, might have more overhead when watercooling or something more extreme. But pay the extra, 6 months later, for a version that can do similar clocks to the bog standard models, meh.
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