Google Chrome different browsers on Google's own suite, commenting on Chrome's "decimating" of the other browsers, but he questioned whether Google's suite was representative of real programs. He stated that Firefox 3.0 performed poorly on recursion-intensive benchmarks, such as those of Google, because the Mozilla team had not implemented recursion-tracing yet. Two weeks after Chrome's launch in 2008, the WebKit team announced a new JavaScript engine, SquirrelFish Extreme, citing a 36% speed improvement over Chrome's V8 engine. Like most major web browsers, Chrome uses DNS prefetching to speed up website lookups, as do other browsers like Firefox, Safari, Internet Explorer (called DNS
Firefox page loads. In the final category, conformance, it was determined that Firefox had "strong" conformance for JavaScript and HTML5. In conclusion, "Tom's Hardware" determined that Firefox was the best browser for Windows 7 OS, but that it only narrowly beat Google Chrome. In June 2013, "Tom's Hardware" again performance tested Firefox 22, Chrome 27, Opera 12, and Internet Explorer 10. They found that Firefox slightly edged out the other browsers in their "performance" index, which examined wait times, JavaScript execution speed, HTML5/CSS3 rendering, and hardware acceleration performance. Firefox also scored the highest on the "non-performance" index, which measured memory efficiency,