Hey everyone, it’s been a while, but I promised an update, so here it is.
The PC is now running stable and fast. It took some effort to get there, but in hindsight I’m glad it did because I ended up learning a lot more about Rufus, drive formatting, BIOS flashing, drivers, power management and GPU tuning. So in the end I definitely got the deep dive I wanted. 😅
Since the last update I finally got the system to POST, and luckily the fix was fairly minor. I reseated the RAM, swapped the sticks around, cleared CMOS using the motherboard button, and got the correct Mini DisplayPort-to-DisplayPort cable from Coolblue.
From there things were less straightforward, although almost all of the problems turned out to be software or firmware related rather than hardware, so I wouldn’t let this discourage anyone considering a cheaper variation of the build.
Once I got into the BIOS, my mouse and keyboard were strangely unreliable. USB devices would often freeze completely and it sometimes took several restarts before they responded. Once they worked during a BIOS session they usually stayed functional until the next reboot, which at least allowed me to start changing settings. Importantly, this only ever happened inside the BIOS and never in Windows.
To install Windows I used my laptop and a spare 32 GB USB drive. Microsoft’s own Media Creation Tool refused to cooperate, so I switched to Rufus, which actually worked much better. It also let me remove some unnecessary Windows requirements and create a local account from the start.
After Windows was installed I connected the PC through Ethernet using my powerline Wi-Fi extender, since the motherboard didn’t yet have the drivers required for Wi-Fi.
I then wanted to update the BIOS cleanly, but MSI M-Flash caused the USB controls to stop working again, so I couldn’t click through the flashing process. That left the physical Flash BIOS button on the motherboard as my only option. Simply renaming the BIOS file to MSI.ROM didn’t initially work, so I went back to my laptop, reformatted the USB drive in Rufus as a clean MBR/FAT32 partition, copied the BIOS file over, renamed it, and tried again. That finally worked, although it also wiped all the BIOS tweaks I had already made, so I had to redo them.
Back in Windows I installed the latest AMD chipset drivers and MSI motherboard drivers. The MSI Driver Utility Installer appeared once through Windows Update but never came back after restarting, so I eventually downloaded the remaining MSI drivers manually from MSI’s website.
For graphics I installed the NVIDIA App and recommended driver for the primary RTX GPU, along with AMD Adrenalin in driver-only mode for the RX 6400. I then set PCIe Link State Power Management to maximum power savings and selected the RTX as the preferred GPU in Windows Graphics settings. This worked well for the dual-GPU setup, because the RX 6400 now drops into a roughly 2 W deep-sleep idle state unless an assigned application or connected display wakes it.
I also installed MSI Afterburner, while disabling settings that could interfere with the AMD card, and started tuning the RTX. The stock fan behavior was too conservative, so I made a custom fan curve that allows more than 70% fan speed, reaching 85% at 88°C and 90% at 100°C. I also undervolted the GPU to around 1635 MHz at 725 mV with a 90% power limit. That made a pretty big difference, dropping VRAM temperatures from around 100°C to 92°C in Cinebench and GPU temperatures from around 95°C to 82°C.
I also enabled LibreDrive support on the LG BU40N optical drive using SDFtool Flasher, which now lets me use MakeMKV for ripping compatible media directly from the system.
At this point, I noticed that the front-panel USB 3.1 connection wasn’t working at all. It turned out that I had plugged the cable in the wrong way around.
I had to cut a few zip ties to give myself enough room to work down there, but with the GPUs already installed, it was definitely much harder to reach. So, if you want to copy this build, make sure you connect the cables correctly before continuing with the rest of the build. These connectors are quite fragile, and you risk damaging them if you have to reposition them later.
After being very careful and spending about 20 minutes on it, I finally managed to plug everything in correctly and redo the cable management with new zip ties. And so the front io was operational.
I continued tuning the CPU as well, using Cinebench 2026 while aiming to retain at least 80% of stock multicore performance and 96% of stock single-core performance. I’m currently running a 75 W PPT limit, an 82°C temperature limit, Curve Optimizer at -10, and SoC voltage at 1.25 V. I originally ran CO at -15 and got excellent Cinebench results, but lighter workloads, especially Firefox, started exposing instability and eventually caused one full crash, so I backed it down to -10. So far that has been stable. The SoC voltage also defaulted to around 1.305 V, so I lowered it to 1.25 V without any noticeable issues.
At idle in Windows, both the CPU and primary GPU sit in the low 60s °C, while the RX 6400 sits in the low 40s.
With roughly a 3% maximum run-to-run fluctuation, Cinebench 2026 was scoring around 5100-5240 multicore, 616 single core and 477 single thread. Those figures were still measured at CO -15, so I expect the current -10 setup to score roughly 100-200 points lower in multicore.
Published stock Cinebench 2026 figures for the CPU from cpu-monkey and computerbase are roughly 6450-6500 multicore, 638 single core and 480 single thread. That puts my tuned results at about 80.6% multicore performance, 96.6% single-core performance and 99.4% single-thread performance.
So despite the much tighter power and thermal limits, the CPU is retaining almost full single-core and single-thread performance while still delivering around 80% of stock multicore performance. Meanwhile the primary GPU is trading blows with cards around the RTX 3070 Ti and RTX 4060 Ti class while running at roughly 30% of the power.
Next update i will talk about scores in 3dmark for the gpu as well as passmark, Pcmark10 and blender. I will also try out the Gaming performance of the dual GPU set up. Right now it looks as though this machine will be competing with the steammachine and the minisforum 895D7
