Who Controls the User Experience? AMD’s Carrizo Thoroughly Tested

Benchmark Overview

For our testing we had each of the laptops at the same time for the best part of a workweek, alongside meetings with AMD to discuss the microarchitecture and platform positioning. Each system was purged into a fresh OS state, and then we applied a high profile performance state for the benchmarking in the air-conditioned lab.

The benchmarks fall into several areas:

Short Form CPU

Our short form testing script uses a straight run through of a mixture of known apps or workloads, and requires about four hours.

Web and Synthetic

The web tests are a usual mix of Octane/Kraken with WebXPRT in the mix. Synthetic CPU testing relates to our long term data under CineBench and x264.

Professional and OpenCL

Our professional tests involve a synthetic workload (PCMark), a 2D to 3D image and model conversion tool used by archivists and modelers (Agisoft in CPU only and OpenCL mode) as well as Linux Bench. Unfortunately Linux Bench only seemed to work on a pair of systems.

Gaming (3DMark, Rocket League)

Due to timing we were only able to run a couple of gaming tests, namely parts of the 3DMark suite and our Rocket League test.

Power and Performance Testing

A portion of our benchmarks were profiled for performance – namely their effect on CPU temperature, frequency and usage – which we will go in to detail over. Both of the HP Elitebooks, the Kaveri and Carrizo units, were also hooked up to a Watts Up PRO monitor for a full shakedown of power consumption on some of the more popular tests. We will go into these in detail.

Thermal Effects

As we have seen in previous laptop benchmarking scenarios, the design of the chassis is an important part in understanding how a processor will react to a workload. Some units have their skin temperature limit set unbearably high in order to get the best performance, whereas others are more restrictive. Carrizo promotes the expansion of both of these facets for either better performance or thermals, so we tested it with a FLIR thermal camera during Rocket League on all five systems as well as some internal recording scripts during a few benchmarks.

A Side Note worth Remembering

One intriguing thing to mention in our testing was background processes. Nominally all efforts are done to minimize these (disable WiFi when not needed, disable updates), however when a system comes preinstalled with Intel McAfee anti-virus, it can be an exercise to remove it. Yes, that’s right – for some odd reason, some of the OEMs systems had Intel McAfee pre-installed. I assume it is because the OEM gets a small kickback for including it on their OS image, therefore either increasing margins or reducing the price of the system. McAfee AV is an example of a simple piece of software that can provide a negative user experience – checking of updates when you least expect it, performing mini-scans of everything coming in and out of an I/O port, and for the systems that have mechanical hard drives with single channel memory, it can be the difference between casually watching a film to having to apologize for why a video is dropping frames. Needless to say, it was obliterated.

The other issue is actually a default windows problem. Whenever certain I/O devices are plugged in/removed, or even at random times, the system will call Windows Defender to start probing files and memory in use. The issue here is multiple – it eats up a thread with mostly integer/string work reducing available resources for the user, but on occasion will bring disk drive utilization to 100%, causing access delays when the user is in the middle of something. While Defender can be a critical part of a safer environment, it boggles my mind that it comes on so freely and robs a poorly configured system of its user experience. It also drains battery life as well. This is a disconnect between software developers writing code suitable for the resources available, OEMs for deciding what hardware would be good for a particular price point and believing users are satisfied with such a user experience, and the hardware manufacturers for not circling back round to test the most relevant use cases. It ends up being a negative loop where no-one works with each other, which benefits no-one (more on this later).

Consequently, for our testing I also turned down Windows Defender's activity/sensitivity on all of the test laptops. My personal (insert subjective experience mode) way of ‘delaying’ Windows Defender is to go to Task Scheduler, go to Microsoft > Windows > Windows Defender and on each of the four options change the conditions to:

- Enable ‘Start the task only if the computer is on AC power’
- Enable ‘Stop if the computer switches to battery power’
- Enable ‘Start the task only if the computer is idle for X minutes’
- Enable ‘Stop if the computer ceases to be idle’

How the system determines a true in-OS idle state is somewhat difficult, as some software will have idle periods before called (e.g. watching an online video) so having it come in after 30 seconds idle isn’t usually beneficial, so I (personally) set it for 10 minutes on lower end systems where responsiveness matters.

The System I Didn’t Get to Benchmark: The Dell Inspiron 3656

As part of my meeting schedule, I was offered an explanation as to what goes behind the scenes in retail marketing from one of the senior account managers. We took a trip to the local Best Buy and I was talked through how most areas of the store are, for lack of a better term, rented out by the retailer to the companies who have strict rules to follow. This applies to store-in-stores, end-caps, focused aisles and even the location within the store can affect the price. It made sense, but we came across this following AMD system:

This is the Dell Inspiron 3656 which, for lack of a better description, is Carrizo in a desktop form factor. I asked if I could peek inside, but for some reason no-one in Best Buy had a screwdriver (as if)! But inside is a mobile focused Carrizo CPU, presumably in 35W mode, with sufficient cooling as well as a discrete Radeon R9 360 graphics card in a PCIe x16 slot. Combine in some other factors such as a 2TB HDD, 16GB of DDR3L-1600 SO-DIMMs and you are good to go.

The 3656, as it turns out, can come with three different AMD Carrizo processors (FX-8800P, A10-8700P, A8-8600P) in a thermally unrestrained environment, which would arguably give the best possible scores. The two things I couldn’t confirm were related to the DRAM. I would have liked to know if the design is a true dual channel design for Carrizo only, or if it shares pin compatibility with Carrizo-L which would limit it to single channel only. Also the memory speed – if it is in 35W mode, this would mean the system could engage DDR3-2133 if it uses appropriate SO-DIMM modules. However, the specifications sheet only mentions DDR3L, which is limited to DDR3L-1600. In a desktop like this, the difference between DDR3L and DDR3 would be minor, and the higher speed memory would help benefit (unless it was Carrizo-L focused).