Before going on to install the ASRock Taichi Z890 OCF motherboard, we thought we’d give our copy of the AMD R7 9800X3D processor a cold run. We have a DOD, also known as a single stage phase change, which allows us to lower the temperature below 0°C. The temperature of our DOD can drop to around -54°C at no load. Of course, when the processor is ‘active’, the temperature will be different.
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But what is a DOD?
When we post photos on social networks, we immediately receive a huge number of questions about this DOD. This one was manufactured by Piotres and sent directly from Poland in May 2013, and as you can see, it’s still perfectly operational.
We won’t go into the technical terms, but the basic principle is to supply cold to the end of the evaporator which will be in contact with either a processor or a GPU. The temperature at the evaporator goes down to -54°C at no load and during our tests with the R7 9800X3D, we’ll see how the temperatures behave.
Necessary insulation:
As we’re going to be dropping temperatures below ambient, we need to insulate our socket to avoid any condensation problems. To do this, we’re going to use several items, charcoal gum and absorbent paper, as well as neoprene to place under the PCB. We won’t go into all the details here, but have a look at our dry ice tutorial if you’re interested.
So here we go for this series of cold tests with the R7 9800X3D.
Our results under watercooling :
We needed a base before starting our tests. Our R7 9800X3D behaves fairly well when overclocked, as we passed most of the benchmarks at 5550 MHz at a voltage of 1.20 volts (LV7). The objective will therefore be to see how far we can go with our DOD.
It’s important to know that even if the temperature of our DOD at the evaporator is -54°C, the temperature of the processor should be around -15/-10°C. We ran a Cinebench R23 at the original frequencies and during this, the frequency became positive again, with a 4 degrees. This is already better than with watercooling, where we were at 60°C.
The good news is that by maintaining a voltage of 1.20 volts, we were able to benchmark Cinebench R23 and Geekbench 3 at 5850 MHz. The temperature became positive, but did not exceed 12°C. It’s therefore important to have good insulation to avoid condensation during these moments when temperatures flirt with the negative and the positive.
See you in a few weeks’ time for a session under LN2 with this R7 9800X3D, which seems to have plenty left in the tank!
