An anonymous reader writes "Tom's Hardware has published a lengthy article and a set of benchmarks on the new "Haswell" CPUs from Intel. It's just a performance preview, but it isn't just more of the same. While it's got the expected 10-15% faster for the same clock speed for integer applications, floating point applications are almost twice as a fast which might be important for digital imaging applications and scientific computing." The serious performance increase has a few caveats: you have to use either AVX2 or FMA3, and then only in code that takes advantage of vectorization. Floating point operations using AVX or plain old SSE3 see more modest increases in performance (in line with integer performance increases).

An anonymous reader writes "Next Saturday from 8:30PM to 9:30PM EST is 'Earth Hour' (0:30 to 1:30 UTC on Sunday). Millions of people will be participating by shutting off their lights for an hour to show they care about the environment. However, according to this article in Slate, Earth Hour is simply 'vain symbolism,' and it won't actually save any energy — quite the opposite. Quoting: 'Notice that you have not been asked to switch off anything really inconvenient, like your heating or air-conditioning, television, computer, mobile phone, or any of the myriad technologies that depend on affordable, plentiful energy electricity and make modern life possible. If switching off the lights for one hour per year really were beneficial, why would we not do it for the other 8,759? Hypothetically, switching off the lights for an hour would cut CO2 emissions from power plants around the world. But, even if everyone in the entire world cut all residential lighting, and this translated entirely into CO2 reduction, it would be the equivalent of China pausing its CO2 emissions for less than four minutes. In fact, Earth Hour will cause emissions to increase. As the United Kingdom's National Grid operators have found, a small decline in electricity consumption does not translate into less energy being pumped into the grid, and therefore will not reduce emissions. Moreover, during Earth Hour, any significant drop in electricity demand will entail a reduction in CO2 emissions during the hour, but it will be offset by the surge from firing up coal or gas stations to restore electricity supplies afterward.'"

Hugh Pickens writes writes "Thomas K. Grose reports that the Environmental Protection Agency (EPA) estimates that greenhouse gas emissions in the US have fallen 8 percent from their 2007 peak to 6,703 million metric tons of CO2 equivalent, due largely to the drop in coal-fired electricity which in 2012 generated 37.4 percent of US electricity, down from 50 percent in 2005. But don't celebrate just yet. A major side effect of that cleaner air in the US has been the further darkening of skies over Europe and Asia as US coal producers have been shipping the most carbon-intensive fuel to energy-hungry markets overseas. US coal exports to China were on track to double last year and demand for US metallurgical coal, the high-heat content coking coal that is used for steelmaking, is so great in Asia that shipments make a round-the-world journey from Appalachia as they are sent by train to the port of Baltimore, where they steam to sea through the Chesapeake Bay, then south across the Atlantic Ocean and around Africa's Cape of Good Hope to reach Asian ports. The Tyndall Center study estimates that the burning of all that exported coal could erase fully half the gains the United States has made in reducing carbon emissions and if the trend continues, the dramatic changes in energy use in the United States — in particular, the switch from coal to newly abundant natural gas for generating electricity — will have only a modest impact on global warming, observers warn. 'Without a meaningful cap on global carbon emissions, the exploitation of shale gas reserves is likely to increase total emissions,' write Dr John Broderick and Prof Kevin Anderson. 'For this not to be the case, consumption of displaced fuels must be reduced globally and remain suppressed indefinitely; in effect displaced coal must stay in the ground (PDF).'"