Friday was a day I was very excited for, but also dreading.
I decided to take a plunge and purchase the Ryzen 9 3900X, upgrading my desktop machine to 12 CPU cores, 24 threads, and the other various performance uplifts that the Ryzen third-generation parts bring – increased instructions per clock, larger caches, big uplift in floating point operations and the ability to properly handle AVX2 code, and the increased clock speeds.
However, I was also extremely nervous because early reports from people who bought the same CPU in-person on the 7/7/2019 launch date showed some problems. Motherboards from the X470 era (including my Asus Crosshair VII Hero Wifi) could have problems depending on BIOS version. My specific motherboard model was using an older AGESA (AMD’s product definitions that are loaded via BIOS) which had some boost frequency problems with the 3900X, and users were reporting instability, issues with memory clocks and timings, the boost problems that many boards had, and loss of their mouse in BIOS and sometimes just loss of their mouse overall.
So I came home from work, the new CPU and a fresh tube of thermal paste in tow, and I was pretty apprehensive, to be honest. I fired up my system with the Ryzen 7 2700X in it for one last time, mainly to warm up the thermal paste currently applied to avoid any issues with the cooler pulling the CPU out of socket. While I was at it, I ran some last minute benchmarks, downloaded new drivers and installed them, and then flashed the motherboard to the newest available BIOS and made sure everything was working with my 2700X before taking the thing apart to replace the CPU.
With the BIOS version I had been using, I was having some instability issues here and there. Sometimes, the system would bootloop in BIOS and force me to intervene. Sometimes, the memory settings didn’t work, even as I only set the frequency in BIOS and allowed the timings to be set loosely by the motherboard. I was able to boot successfully and quickly with the new BIOS into my system using the 2700X, and that allayed some of my fears.
So, I took a deep breath, powered off my system, and removed all the paneling. I put it on its side, grabbed my electric screwdriver along with paper towels and isopropyl, and set about my work. The 2700X left a small booger of thermal paste that almost got into the socket, which scared me! I wiped desperately at the socket to remove the extra paste, and it was thankfully gone. I picked up the new CPU, trying not to think about what could go wrong, and dropped it into the socket, latching down the retaining arm with a satisfying click. I applied a new layer of thermal paste, trying to outline the chiplet layout underneath by using a large line over the two core chiplets and an X over the IO chiplet, although I later learned that the parts are likely rotated 90 degrees from where I thought they were underneath the heatspreader, oops!
My NZXT Kraken X72 mounted easily enough to the CPU, only needing two passes because the tube tension the first time made me miss a mounting post. I hand-tightened the mounting caps on the 4 posts, and then used the electric screwdriver carefully to apply a bit more tension. I took the chance to loosen two intake fans at the bottom of the case, which had screw tightness that would sometimes flex the steel of the case in to the path of a fan blade and make a very unpleasant grinding noise. I left all the side and top panels off, set the system upright, and powered it on, holding my breath the whole time.
First boot on a Ryzen system always takes a moment, because the BIOS realizes something changed, but every second felt like agony, waiting and waiting for the system to power on. Finally, I got normal post codes on the seven-segment display on the motherboard, and a setup screen telling me that my CPU had changed (oh really, what a surprise). It knew the CPU by model name, which was my first sigh of relief, and when I went in to play with BIOS settings, it was reporting a relatively normal temperature for the CPU! Even from switching CPUs, a handful of changes emerged in BIOS – my options for Precision Boost Overdrive were in a new place, with additional options alongside them. My PCI-Express slot options had a new choice for PCIE 4.0 speeds, which is not supposed to be allowed on older motherboards, but there it was. I also heard there were problems with GeForce cards and Samsung NVME SSDs using auto settings here, so as the owner of both (lucky me, all the problem children in one system!), I set the PCIE mode to 3.0 standard to avoid those issues.
I then got into Windows and it was pretty normal, nothing unusual happening, although my CAM software I begrudgingly use with my CPU liquid cooler wouldn’t report any temperature from my CPU or GPU, and my graphics card under the new Nvidia driver was actually using an idle mode for memory and GPU clockspeed, clocking all the way down to 162 MHz while I sat at the desktop. After a quick reinstall of the Nvidia drivers out of an abundance of caution and an update in CAM version, I had working GPU reporting in CAM again, and while my CPU was not reporting temperature to CAM, it was at least showing 50 degrees at all times, which is probably not unrealistic!
I let the system sit on for a moment while I installed my now old Ryzen 7 2700X into my girlfriend’s PC and made sure that worked (her’s took longer because the Wraith Prism installation mechanism is awful if you have large hands). Once that was done, I did a few diagnostic checks on my system – making sure my RAM speed was right, that I wasn’t getting any of the WHEA errors in Windows that hide in the event log and were the causes of some performance degradations with Geforce cards and Samsung NVME drives, and I noticed only one problem – my RAM timings at the rated DDR4-3200 were awful. When I let the motherboard do timings itself on the 2700X, it gave me a CAS latency of 18, which was not the best, but not awful. On the 3900X, the motherboard decided CAS latency was up to 22, which, given the more memory-sensitive nature of Ryzen third-gen and especially how dependent the 3900X is on good timings, was not great.
I decided to reboot one more time and try something I never got to work on the 2700X – using the XMP timings built in to the memory. I could run the RAM at 3200 on my 2700X with no issues, but the second I tried to tweak the timings to a more performant level, I’d eventually run into bluescreens and application crashes having to do with memory accesses. I assumed (perhaps wrongly) that my memory was just bad for the rated speeds at XMP, and let the auto-timings carry on since they weren’t so much slower than rated. I turned on the XMP profile under the 3900X, and…it worked! Not only did it work, but it runs really well, passed a multi-loop Memtest 64 run, and has allowed me to play WoW and FFXIV for hours without any crashes and run Windows with no BSODs at all. When AMD said that the new integrated memory controller in the third-gen Ryzen parts was better, they were not kidding – it runs substantially better than I expected, as I did not anticipate being able to even run XMP timings on it!
With that done, I benchmarked the performance of the new system with the Shadowbringers FFXIV benchmark and Cinebench R15, and the results weren’t a surprise – my Shadowbringers improvement was only 300 more points added to a base score of 17,200, while my Cinebench score shot up by over 50%.
Why Buy a 12-Core CPU, Anyways?
So after writing my upgrade story like, well, a story, I figured something worth addressing is the reason anyone would even want a 12-core CPU when the primary activity they do is playing games.
For me, the 12-core offered two big things I really wanted, one of which makes a lot of sense (provided I follow-through) and the second of which is completely foolish and rooted in a desire to not have a perceived “downgrade” from my prior system.
The good reason first: the 12-core Ryzen 9 3900X is one of the strongest performers in multimedia workloads available on a consumer-level platform today. In a future where my goal is to do more streaming and video capture and editing of my gameplay, the best choice is the 12-core 3900X, without moving to the high-end Threadripper platform or to Intel’s X299 platform.
In testing I did this weekend, I can locally capture footage at 4k resolution, 60 frames per second, with really high quality settings, and have 0 perceived impact to my gameplay experience. When looking at framerate counts using various tools, there is a small hit to framerate, but since the baseline for my system clears the refresh rate of my monitor most of the time, the loss of performance cannot be noticed, which is a drastic change from my 2700X, which had me scrambling to 1080p60 at lower bitrates to accommodate. It chews through video renders in Adobe Premiere, cutting a ton of time off of my average YouTube render, which is good, since I have around 6 weeks worth of LP episode footage saved up. 3D rendering I do in SketchUp just for fun is smoother and more responsive.
It also tends to run cooler than my 2700X under my average gaming load – I can play WoW or FFXIV while also watching YouTube and the CPU runs around 3 degrees cooler during that workload, although when a lot of activity happens, the peak temperature is higher (the hottest my 2700X got in gaming was around 58 degrees Celcius, while the 3900X hit 64 degrees).
Now, for the irrational reason – if you’ve read some of my older posts from around this time last year, when I first moved to the AMD Ryzen platform, the big thing I talked about was how out of the game I was with new technology, since I last bought a system for myself in 2011. The reason that worked is because my 2011 system was a peculiar beast – built in a sudden windfall, it used EVGA’s legendary Classified SR-2 dual-socket motherboard and a pair of six-core Xeon server chips to reach…12 cores, and 24 threads. Now, to be fair, the Ryzen 7 2700X has enough of an IPC uplift over that era of Xeon that even with the core-count downgrade (and assuming we set the Ryzen to the same clockspeed of 2.4 GHz), it would still be faster by a fair amount compared to that system.
Well, I knew that mentally, the opportunity to make a single purchase for my new system to bring it back to core-count parity with my prior gaming rig would be too hard to resist, and so as rumors escalated around what the third-generation Ryzen lineup would contain, I knew that I was going to end up staring down what was eventually labeled the Ryzen 9 3900X and when that day came, I would likely buy it. I waited overnight for reviews on Saturday 7/6, and although none came, before I called it for bed, the CPU was available to purchase on Newegg, and I had to jump in and buy it – reviews be damned. Lucky me, too – getting one now is a much harder feat. It was (and is) an irrational act, with a theoretical payoff at some point (if I actually get serious about content creation, this CPU will be a worthy investment) – but I knew that given the financial ability to give in to my desire to return to a 12-core system, I would, and so even though the possibility existed that reviews for the 3900X might not be so great, I still took the leap.
After a full weekend of vegetative gaming and benchmarking, I am happy to report that I do not regret the investment so far. I’ve gotten smoother gameplay through more stable frametimes, even if the top-end improvement in maximum framerate isn’t that high. My attempts at using producitivity software shows that the new Ryzen generation is an absolute beast, owing to the multitude of performance improvements (IPC increases would have improved performance at identical clocks anyways, and then they also have higher clockspeeds and more cores). The newfound ability to run XMP timings on my memory is a welcome surprise, as is the lower average load temperature and my amusement at seeing games that would load my 2700X up to 20% utilization fail to break 10% on the new CPU.
Overall, I’m really happy with my purchase, and while I wouldn’t recommend the 3900X specifically to everyone I know, the Ryzen third-generation lineup delivers a substantial improvement that escapes the bounds of a simple generational uplift.
It also helps that I can sell my selfish act of winning dick-waving contests around core count as the means by which I made my girlfriend’s PC much better!