CPU Tests: Synthetic

Most of the people in our industry have a love/hate relationship when it comes to synthetic tests. On the one hand, they’re often good for quick summaries of performance and are easy to use, but most of the time the tests aren’t related to any real software. Synthetic tests are often very good at burrowing down to a specific set of instructions and maximizing the performance out of those. Due to requests from a number of our readers, we have the following synthetic tests.

Linux OpenSSL Speed: SHA256

One of our readers reached out in early 2020 and stated that he was interested in looking at OpenSSL hashing rates in Linux. Luckily OpenSSL in Linux has a function called ‘speed’ that allows the user to determine how fast the system is for any given hashing algorithm, as well as signing and verifying messages.

OpenSSL offers a lot of algorithms to choose from, and based on a quick Twitter poll, we narrowed it down to the following:

  1. rsa2048 sign and rsa2048 verify
  2. sha256 at 8K block size
  3. md5 at 8K block size

For each of these tests, we run them in single thread and multithreaded mode. All the graphs are in our benchmark database, Bench, and we use the sha256 results in published reviews.

(8-3c) Linux OpenSSL Speed sha256 8K Block (1T)(8-4c) Linux OpenSSL Speed sha256 8K Block (nT)

GeekBench 5: Link

As a common tool for cross-platform testing between mobile, PC, and Mac, GeekBench is an ultimate exercise in synthetic testing across a range of algorithms looking for peak throughput. Tests include encryption, compression, fast Fourier transform, memory operations, n-body physics, matrix operations, histogram manipulation, and HTML parsing.

I’m including this test due to popular demand, although the results do come across as overly synthetic, and a lot of users often put a lot of weight behind the test due to the fact that it is compiled across different platforms (although with different compilers).

We have both GB5 and GB4 results in our benchmark database. GB5 was introduced to our test suite after already having tested ~25 CPUs, and so the results are a little sporadic by comparison. These spots will be filled in when we retest any of the CPUs.

(8-1c) Geekbench 5 Single Thread(8-1d) Geekbench 5 Multi-Thread


SPEC2017 and SPEC2006 is a series of standardized tests used to probe the overall performance between different systems, different architectures, different microarchitectures, and setups. The code has to be compiled, and then the results can be submitted to an online database for comparison. It covers a range of integer and floating point workloads, and can be very optimized for each CPU, so it is important to check how the benchmarks are being compiled and run.

We run the tests in a harness built through Windows Subsystem for Linux, developed by our own Andrei Frumusanu. WSL has some odd quirks, with one test not running due to a WSL fixed stack size, but for like-for-like testing is good enough. SPEC2006 is deprecated in favor of 2017, but remains an interesting comparison point in our data. Because our scores aren’t official submissions, as per SPEC guidelines we have to declare them as internal estimates from our part.

For compilers, we use LLVM both for C/C++ and Fortan tests, and for Fortran we’re using the Flang compiler. The rationale of using LLVM over GCC is better cross-platform comparisons to platforms that have only have LLVM support and future articles where we’ll investigate this aspect more. We’re not considering closed-sourced compilers such as MSVC or ICC.

clang version 10.0.0
-Ofast -fomit-frame-pointer
-mfma -mavx -mavx2

Our compiler flags are straightforward, with basic –Ofast and relevant ISA switches to allow for AVX2 instructions. We decided to build our SPEC binaries on AVX2, which puts a limit on Haswell as how old we can go before the testing will fall over. This also means we don’t have AVX512 binaries, primarily because in order to get the best performance, the AVX-512 intrinsic should be packed by a proper expert, as with our AVX-512 benchmark. All of the major vendors, AMD, Intel, and Arm, all support the way in which we are testing SPEC.

To note, the requirements for the SPEC licence state that any benchmark results from SPEC have to be labelled ‘estimated’ until they are verified on the SPEC website as a meaningful representation of the expected performance. This is most often done by the big companies and OEMs to showcase performance to customers, however is quite over the top for what we do as reviewers.

For each of the SPEC targets we are doing, SPEC2006 1T, SPEC2017 1T, and SPEC2017 nT, rather than publish all the separate test data in our reviews, we are going to condense it down into a few interesting data points. The full per-test values are in our benchmark database.

(9-0a) SPEC2006 1T Geomean Total(9-0b) SPEC2017 1T Geomean Total(9-0c) SPEC2017 nT Geomean Total

We’re still running the tests for the Ryzen 5 5600G and Ryzen 3 5300G, but the Ryzen 7 5700G scores strong.

CPU Tests: Legacy and Web Discrete GPU Gaming Tests: 1080p Max with RTX 2080 Ti


View All Comments

  • Cooe - Friday, August 6, 2021 - link

    The recent GPU driver additions were NOT for Rembrandt. My guess is that's from some as of yet unannounced custom/embedded part for a market/use case where die size is absolutely CRITICAL (the only reason to pick RDNA over RDNA 2 is raw transistor density), that we're seeing there. Rembrandt otoh has had explicitly "RDNA 2" based graphics IP literally since it very first appeared on leaked AMD roadmaps YEARS ago, and it's consistently stayed "RDNA 2" in every future appearance/leaked roadmap.

    In fact with AMD's penchant for copy-pastaing reusable IP blocks across as many different products as they can, the iGPU implementation on Rembrandt is likely to be EXTREMELY similar to what is currently seen on Van Gogh (in fact, it wouldn't surprise me at ALL if they end up just sharing the exact same 8CU RDNA 2 iGPU block wholesale).
  • nandnandnand - Saturday, August 7, 2021 - link


    "Van Gogh is said to have eight compute units (CUs) per shader array with a 1 MB L2 cache while Rembrandt will have six CUs per shader array with 2 MB L2 cache, with the added cache possibly translating into improved gaming performance. It must be noted here that we still do not know the total number of CUs on the GPU, but rumors indicate up to 12 CUs for Rembrandt."
  • AThomas - Wednesday, August 4, 2021 - link

    These APU's have my exact use case. Upgrading my HTPC which has trouble with HEVC codec (YouTube 4K) that can easily play PS2, PS1, Dreamcast, Sega 32X/CD, etc, etc. Plus Space Engineers which none of my rigs can play at the moment. All done with the iGPU at 60+FPS or better , also some Xbox titles like Forza Horizon since I don't play on buying a Xbox X.

    Second use is server. WIth a couple of VM's but mostly containers. Maybe throw a GPU in their for renting out GPU. All those threads will allow lots of functional task to be done.
  • Jorgp2 - Thursday, August 5, 2021 - link

    AMDs APUs don't support GPU virtualization Reply
  • GreenReaper - Sunday, August 15, 2021 - link

    Not yet, no. Reply
  • boozed - Wednesday, August 4, 2021 - link

    Are you sure? Reply
  • eastcoast_pete - Thursday, August 5, 2021 - link

    Hush now! Ian was spilling Intel's newest acquisition plans.. Reply
  • ballsystemlord - Wednesday, August 4, 2021 - link

    In addition to what Dan said above your table entitled, "Ryzen 5 APUs (65W)" Is completely wrong. The 5600G is a 6 core processor and I suspect some of the other entries are incorrect also. Reply
  • Rudde - Wednesday, August 4, 2021 - link

    "The second part is a Ryzen 5 5600G, featuring six cores and sixteen threads, with a base frequency of 3.9 GHz and a turbo frequency of 4.6 GHz. "
    This sentence has suffered from some copy and pasting. 12 threads and 4.4 GHz boost.
  • nandnandnand - Wednesday, August 4, 2021 - link

    "However slow quad cores (like the 2400G still let you down."

    Missing closing parenthesis mark.

Log in

Don't have an account? Sign up now