Anand's Google Nexus One Review
by Anand Lal Shimpi on April 3, 2010 3:40 AM EST- Posted in
- Smartphones
- Mobile
Inside Snapdragon is a Scorpion
Several years ago Qualcomm assembled an architecture team in the Research Triangle Park in NC, coincidentally around 30 minutes from where I live. One of their tasks was to design a high performance CPU core around the ARMv7 instruction set. They called it Scorpion.
While the Scorpion core is normally referred to as a Cortex A8, Qualcomm views it as more of a Cortex A9 competitor. The truth, as always, lies somewhere in between. Like the Cortex A8, Scorpion is a dual-issue in-order microprocessor architecture. As I mentioned in my iPhone 3GS article, you can think of it as a modern day Pentium processor (but not an Atom).
Qualcomm claims the ability to do some things out of order, but by and large the pipeline is in order which ultimately keeps it out of the A9 classification.
Qualcomm hasn't shared much about the base architecture other than to say that it's definitely not based on the Cortex A8. It might have a deeper pipeline than the Cortex A8 to help it reach higher clock speeds. Unlike the ~600MHz target the A8 will hit at 65nm, Qualcomm's Scorpion will run at 1GHz at 65nm.
Scorpion also implements the NEON extensions to the ARMv7 ISA, although Qualcomm's implementation is a higher throughput version of what the Cortex A8 offers. It's my understanding that NEON isn't very widespread in usage today, so I'm not sure that Qualcomm's advantage here matters just yet.
Cache sizes are unknown but I'd expect that they're competitive with what we've seen from competing Cortex A8 implementations. Ultimately everyone is bound by die size and power consumption at 65nm.
Qualcomm integrates the Scorpion core in its Snapdragon SoC. The version of Snapdragon in the Nexus One is the QSD8250. This SoC includes a 1GHz Scorpion core and an integrated 3G modem. The QSD8650 will be used in the Verizon version with support for EVDO and CDMA 2000.
Qualcomm's integrated modem is a very different approach from what we've seen from companies like NVIDIA, Apple/Samsung and TI. Those companies rely on an external modem solution to reduce time to market. Qualcomm's response is to instead offer an SoC that integrates support for all major wireless standards. The QSD8250 used in AT&T's supports GSM, GPRS, EDGE and HPSA networks. The QSD8650 supports CDMA2000 1X, 1xEV-DO Rel 0/A/B, GSM, GPRS, EDGE and HSPA wireless networks.
When I spoke with Qualcomm one message it stressed was how calculated the timing of Snapdragon was. It's not by accident that all of the major Android phones being announced today use Snapdragon, it's because of very careful timing and planning that Qualcom was able to hit this bulge in the market. Most SoC makers would cite time to market as a reason for not integrating a modem into an application processor, it's clear that Qualcomm faced that challenge and took timing very seriously with Snap Dragon.
The CPU side of the Snapdragon SoC is fast. Faster than what's in the iPhone 3GS, Palm Pre and Motrola Droid. Unfortunately there are other issues. Qualcomm scaled up processing speed but didn't increase memory bandwidth. The Snapdragon still has a 32-bit LPDDR1 interface, giving it the same memory bandwidth as its competitors despite boasting a much higher clock speed.
The even bigger problem with Snapdragon is its use of the Adreno 200, a dated and slow GPU Qualcomm acquired from ATI a couple of years ago. Luckily for Qualcomm, intensive 3D gaming hasn't really taken off on smartphones just yet but here Snapdragon is at a disadvantage to the Samsung and TI SoCs that use Imagination Tech's PowerVR SGX.
So the Nexus One has better CPU performance, identical memory bandwidth and worse GPU performance compared to the iPhone 3GS. Nothing is ever easy in this world.
Later this year Qualcomm will introduce its 45nm Snapdragon SoCs. These will range from being simple clock bumps of the 8650 in the Nexus One with LPDDR2 support, to full fledged dual-core versions with a much higher performance 3D core. Qualcomm also confirmed its intentions to move to an out-of-order architecture at some point in the future. I'd expect to hear more about that next year.
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Antioch18x - Saturday, April 3, 2010 - link
Not only that but I didn't see mention of using a background task killer with "auto kill." (But, granted, I didn't *read* the whole article as I already own a N1 and didn't need to see your impressions of it). Due to the Android's method of multitasking, many times you don't actually exit an app when you think you do - it continues running in the background. You really do need a background task auto-killer to get the best battery life. This is one flaw, I think, in Android.Anyways, keeping this in mind I find that your battery life tests may be off. I get better battery life on my N1 than the old iPhone 3G.
spideryk - Saturday, April 3, 2010 - link
There are alternative keyboards available for the android. as of right now swype keyboard is the best available means of entering text on a smart phone. once you get used to swype, you only need one hand to type and most of the time do not need to look at the keyboard to type. a must have on android.bob1939 - Sunday, April 4, 2010 - link
Great review as usual but you missed something I consider critical. The lack of support for hands free bluetooth dialing.Where I live it can cost $180 if you are caught using a handheld phone while driving, so Hands Free dialing is a must.
Worse Google insists in calling his shortcoming an enhancement and shows no sign of fixing it in the near term.
For me this is a showstopper.
Bob Benedetti
dvinnen - Sunday, April 4, 2010 - link
Not sure what you mean by blue tooth dialing but there is certainly voice dialing. The whole voice integration in Android is really fantastic as Anand said in his review.bob1939 - Sunday, April 4, 2010 - link
I mean leave the phone in your pocket and press the button on the steering wheel, on the bluetooth speaker or bluetooth earpiece and say call whoever and the phone dials the number.My understanding of the N1 and other Android 2.1 devices is that you have to press something at least twice on the phone to operate the voice dial. Where I live that will cost $180 if you are seen by a cop fiddling with the phone while driving.
Bob Benedetti
LongTimePCUser - Wednesday, April 14, 2010 - link
I have a Motorola Droid and a 2006 Toyota Prius.The Droid connects via BlueTooth with the Prius.
I can dial a phone number on the Droid from the Prius touch screen.
joe6 - Sunday, April 4, 2010 - link
1) Good: Nexus One has a microSD card slot. Big advantage in my book.2) Bad: Nexus One doesn't support Exchange/Outlook calendar sync without going through the Google cloud services. This is just silly and frankly, kills the deal for me. I think most Nexus One RMAs come from this bullet alone.
Pitne - Monday, April 5, 2010 - link
There an app for this. How do you people miss the point that is android? Android is all about being open and not LOCKED DOWN like apple. So go download the more functional exchange apps and STFUCali3350 - Sunday, April 4, 2010 - link
Not sure if you posted it and I missed it or if you simply don't want to say in a public forum (which is understandable) but which do you , Anand, see yourself using in the future - the Nexus One or the iPhone 3GS? That sort of message says a lot about the current state of the platforms.Anand Lal Shimpi - Sunday, April 4, 2010 - link
Honestly, I'm torn.After the review I switched back to the 3GS because of the simplicity and the keyboard (I type a *lot*). In doing so, I miss the screen, form factor (ugh it was painful holding the iPhone to my head for an hour long phonecall vs. the Nexus One), some of the apps/features and the speed of the Nexus One. Today my answer would be the 3GS, but after using the Nexus One so much over the past few weeks I have to say that some aspects of the iPhone really do feel archaic.
What I may do going forward is continue to alternate between the two to get a better feel for their respective strengths and weaknesses.
Take care,
Anand