Amazon’s new Kindle Fire HD tablets could have an updated quad-core processor and higher resolution (even better than that of the current 8.9-inch model pictured here). Inc. (NASDAQ:AMZN) is reportedly introducing a faster, higher-resolution Kindle Fire HD, which may have been confirmed by a series of graphics benchmark test results leaked online. Two different tablets appear in the test, code-named Apollo and Thor, with each running a quad-core, 2.15 GHz Snapdragon 800 processor from Qualcomm Inc. (NASDAQ:QCOM).

If the GFXBench benchmark test results are accurate, they put the next-generation Kindle HD tablets ahead of the newest Nexus 7 from Google Inc. (NASDAQ:GOOG) in processing power. The stock Android tablet features a 1.5 GHz quad-core central processing unit from Qualcomm. The processor clock speeds listed in the benchmark test results correlate with an earlier report by BGR, which said the new Kindle Fire HD models would also contain 2 GB of RAM.

The Kindle Fire HD tablet code-named Apollo is listed with a screen resolution of 2560 x 1600 pixels, indicating it may replace the 8.9-inch Kindle Fire HD as it increases the resolution by 33 percent for clearer video, images and text. The Kindle Fire HD tablet code-named Thor is listed with a screen resolution of 1920 x 1200 pixels, which represents a 50 percent increase in screen resolution over the 7-inch Kindle HD and matches the resolution of the second-generation Nexus 7 tablet released by Google in July.

Clearly, Amazon appears to favor mythological naming conventions when code-naming its devices.

Amazon announced the first-generation Kindle Fire HD tablets last Sept. 7. Like automobiles, consumer-electronic devices are frequently brought up-to-date annually, and the benchmark test results suggest Amazon will soon announce new versions of the Kindle Fire HD to compete not only with the Nexus 7 from Google but also with the iPad and iPad mini from Apple Inc. (NASDAQ:AAPL).

With respect to the new Kindle Fire HD tablets’ cameras, and the 7-inch model (Thor) will have a front-facing camera, while the 8.9-inch model (Apollo) will have both front- and rear-facing cameras, according to BGR.

Benchmark test results that leak online can sometimes be sources of unreleased information, but they can also be wrong or misleading. The Amazon Kindle Fire HD tablets that appeared in the benchmark were shown running Android 4.2.2, but the company is expected to continue using a forked version of the mobile operating system that does not allow access to the Google Play store.

Amazon updated its Silk Web browser for Kindle devices on Monday, giving the application a new user interface and adding a “reading view” that simplifies text on Web pages and removes advertisements, among other changes.

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