As you know, Intel’s 12th generation Alder Lake processors were launched with the brand new LGA1700 socket design. While the number of pins increased with this socket, the general structure of the processor also changed, resulting in a rectangular rather than square structure.
New processors are not directly compatible with older coolers and additional mounting kits are required from manufacturers. In this regard, various cooling issues even if we use the coolers with the new Alder Lake CPUs livable.
Even high-end liquid coolers can perform very poorly because the coolers sit poorly on the processor. Meanwhile, the reports come not only from users’ feedback, but also from board partners, cooler manufacturers, and system integrators.
So what is the root cause of these problems?
Are the heat emitters excessively curved or is the socket unstable? Other than that, are the pressures at the contact too high or are the cooling systems bad? There can also be talk of very thin and flexible circuit boards, and again it can be difficult to come up with a clear solution. Because these cooling problems are likely a combination of several factors.
In previous reviews, the heat spreader of the new Intel CPUs was said to be fairly flat and not particularly curved. However, even heatsink manufacturers like Noctua have noticed that the coldplate/heatsink support and thus the usable surface for cooling is uneven. On the other hand, different cooler manufacturers are aware of this problem and even the return cases related to insufficient cooling are said to be on the rise.
A heatsink removed from an Intel 12th Gen processor.
Depending on the liquid cooling, processor and motherboard on this issue, a difference of up to 9 degrees was observed between the cooling setups. Also, the thermal paste image after disassembly looked very different. You can see an example in the picture above.
Protrusions on the Processor
Judging by many complaints, the heat spreaders of the processors have an outward curved structure. You can take a look at the screenshots below as this is proven with some measurements made. It was also noticed that many of the tested CPUs were curved inward.
12th Generation surface painting extracted with a 3D profilometer.
Let’s take a look at a CPU with an inward collapsed IHS. If you look at the above measurement made with the 3D profilometer, you can see the defect on the IHS surface. Again, the situation can be clearly seen with the ruler below.
Post-Installation CPU Flexibility
As you can see very clearly in the image below, the heat spreader of the processor not only has an upward projection, but almost the entire CPU is bent.
The next image shows that the thermal paste is also distributed very unevenly thanks to such slopes. Assemblies with the liquid cooling block and the manufacturer’s standard backplate naturally experienced various problems. In the end, the cooler cannot fully perform its duty and an efficient cooling does not occur.
But if even high end heatsinks are causing problems when assembled with genuine parts, then there must be other reasons besides contact pressure and thermal paste.
Twist in Socket
In addition, a standard mount was made with the ASRock Z690 Extreme motherboard. The motherboard’s socket was perfectly straight and free of any curvature before installing the processor. Even tightening the latch after inserting the chip can cause the socket to bend. So it is possible that socket bends are behind these cooling problems.
The ridges extend on all sides so that the edges are more affected. Also, this kink is not present in one area and looks less obvious on the I/O shield side than on the RAM side.
To summarize, thin PCBs can be used in motherboards, depending on the manufacturer and model. Even before installing a processor, U-shaped protrusions can be observed around the socket.
Workaround: Stabilizer Backplate
Besides all these possible causes, a stabilizer backplate can be used that was not originally designed for this purpose and can solve almost all problems. As an example, you can see the Aqua Computer branded liquid cooling plate below.
The cooling solution for the 12th Generation: Backplate.
The look isn’t very pretty, but with a little bit of work it’s possible to mount this plate to the motherboard and prevent the PCB from bending. It is also useful to make this plate when the socket is empty, not when the CPU is plugged in.
Conclusion and Summary
Intel’s new socket LGA-1700 may certainly be well thought out. However, the material some manufacturers use for the socket holder is too soft. At least it can’t provide the necessary pressure to lock the CPU and screw the heatsink down.
Most unused CPUs have an almost flat heat spreader (IHS). Some flakes can have outward and inward slopes. The slightly curved IHS and CPU curvature on the socket ultimately negatively impacts cooling performance. This topic continues to be discussed by manufacturers and forums. A possible workaround is to use a backplate as we mentioned above.
Update: New Method and Temperature Tests
Switching from the LGA1200 socket to the LGA1700 socket resulted in a 42% increase in the number of pins, resulting in a longer socket. As a result, Alder Lake chips are larger and more rectangular than Rocket Lake, which is smaller and more square in shape.
Igor says the problem with the new processors is related to Loading Mechanism (ILM) ILM still locks onto Alder Lake processors at the same pressure points as Rocket Lake. As a result, the mechanism pushes the processor down from the center and the edges are more airborne. The integrated heat spreader (IHS) of the Alder Lake CPU, on the other hand, takes a concave shape after a few hours of operation.
To illustrate this, Igor’s Lab displayed an Alder Lake processor with hundreds of hours of operation. You can see that the processor presents a concave shape at the top and a convex shape at the bottom. In other words, the processor appears to be slightly bent along the points where the ILM exerts pressure.
Igor mentioned a backplate solution to the bottom of the motherboard in this thread. Now a new solution has been found that can be used: the washer that can be applied to the 4 corners.
The concave structure of the IHS prevents the base plate of the CPU cooler from making direct contact. So the heat has to travel a longer distance with the thermal compound than the gap. This solution ensures that the CPU cooler has optimal contact.
You only need to add a few M4 washers to the socket holder to reduce mounting pressure. The first step requires removing the four M4 Torx T20 screws holding the ILM in place. In the second step, we place the M4 washers in each screw hole. Finally, it is enough to replace the four screws and screw them in.
Igor’s Lab measured the temperature of the Core i9-12900K’s P-cores at 500 ms intervals with the HWiNFO utility. The broadcast used the popular Prime95 software with Small FFTs preset and AVX2 (FMA3) as a five-minute stress test.
| Ron dela |
P0 max Δ | P1 max Δ | P2 max Δ | P3 max Δ | P4 max Δ | P5 max Δ | P6 max Δ | P7 max Δ | Middle lama |
Arrival me |
|---|---|---|---|---|---|---|---|---|---|---|
| Stock | 69.5 | 82.5 | 73.7 | 86.6 | 75 | 83.6 | 73.7 | 74.8 | 76.64 | – |
| 0.5mm | 66.4 | 79.1 | 70.2 | 83.7 | 72.3 | 79 | 69.3 | 70.7 | 73.84 | -2.8 |
| 0.8mm | 67.1 | 77.9 | 70.2 | 82.6 | 72.3 | 78.4 | 70.2 | 70.5 | 73.65 | -2.99 |
| 1.0mm | 63.9 | 74.8 | 67.2 | 79.3 | 69.3 | 77.4 | 67 | 68.1 | 70.88 | -5.76 |
| 1.3mm | 64.2 | 75.2 | 68.1 | 80.1 | 70.2 | 77.9 | 68.1 | 69 | 71.6 | -5.04 |
The experiment was carried out with M4 washers of different sizes, but 1 mm thick ones gave the best results, reducing the temperature by 5.76 degrees. Also, it is not possible to say that thicker ones are better.
