For just over a week, I’ve been using two phones interchangeably. The first is the Lava Xolo X900 with Medfield inside, the second is the flagship of HTC’s new One series, the HTC One X on AT&T. It’s a device with lofty goals, as it’s the flagship of HTC’s new branding and strategic positioning behind a single line of devices, industrial design, and focus. The strategy mirrors that of Samsung’s with their Galaxy series, and if successful will rekindle the excitement behind HTC’s brand.

The One X on AT&T is really a One XL (L for LTE), however in the USA the device carries full One X branding. We’ve got the International One X and One S variants which will be reviewed in short order, but for today we’re talking specifically about the One X on AT&T. Read on for the full review.

Yesterday we presented the first results of Qualcomm's Krait based MSM8960 SoC. While we still await the first Krait based phones (widely expected to begin shipping sometime in Q2), courtesy of Qualcomm's MSM8960 Mobile Development Platform we were able to get a good idea of the upper bound for Krait and MSM8960 performance. I mention it's the upper bound because, at least in the past, MDP performance hasn't corresponded directly to shipping device performance. There was a pretty big delta between MSM8660 MDP performance and phones that used the MSM8660. Qualcomm tells us that this time around things are going to be different. Qualcomm is expecting a much narrower (nonexistent?) gap between the MSM8960 development platform and phones that use MSM8960 silicon. One major difference between the MSM8960 MDP and our earlier MSM8660 MDP was the state of the CPU governor. In the earlier MDP the governer was set to max performance, always delivering the CPU's maximum clock frequency. With the MSM8960 platform the governor was set to ondemand, allowing for variable CPU speeds depending on what the OS requests of the device. The ondemand setting is in-line with what we can expect device manufacturers to use when they ship phones. All of this goes to say that while we have a good handle of what Krait and the MSM8960 are capable of, there are still a lot of unknowns.

While it's true that shipping performance remains to be seen, some of the deltas we saw between MSM8960 and the current competition were so great that even a much slower implementation in a shipping phone would still be significantly faster than anything else out today.

We left our MSM8960 investigation with two major unknowns. The first was power consumption. We still haven't been able to get Qualcomm's Trepn tool running on the MSM8660 MDP, which has always been a bit finicky. To get a true feel for MSM8960 battery life we will have to wait for shipping devices. The other major unknown was really how MSM8960 stacks up against NVIDIA's Tegra 3.

Tegra 3 was everything Tegra 2 should have been. We got higher clocks, NEON support and a much faster GPU. The only thing missing from Tegra 3 was a dual channel memory interface. We were happy with Tegra 3 on ASUS' Eee Pad Transformer Prime, but in less than a week we'll get to meet some of the first smartphones based on T3 silicon.

Armed with the Eee Pad Transformer Prime (updated to Ice Cream Sandwich) we're able to get a rough idea of how these two heavyweights will compare. The same caveats that applied to the MDP apply to our Tegra 3 platform as well. Since we are using a tablet we're obviously dealing with a higher TDP than what you'll find in a phone. The comparison today is largely academic and naturally shipping devices may be better or worse that these two representatives. With the disclaimers out of the way, let's get to the comparison.

If you've been following our SoC and smartphone related coverage over the past couple of years, you'll probably remember how Qualcomm let us take home an MDP8660 from MWC 2011 and thoroughly benchmark it. Qualcomm has done essentially the same thing this year, this time sending their latest and greatest MSM8960 SoC inside the aptly named MSM8960 Mobile Development Platform (MDP) just before MWC 2012.

The timing is impeccable as we're fully expecting to start seeing MSM8960 based phones next week at MWC, and we've been telling you to hold off on any smartphone purchases until the 8960's arrival. Today we're finally able to give you an indication of just how fast Qualcomm's next-generation Snapdragon S4 will be. Read on!