It just seems like every thread that has to do with temperatures on Intel's mainstream CPU's that someone is knocking on intel because they use paste instead of soldering. After doing a bit of research, there are more variables than just TIM which causes high temperatures, and a whole lot of reasons why they aren't soldering their mainstream CPUs. I believe that we should all read this great article before hating on Intel's decision on using TIM.
In short, it isn't as easy as just melting on some solder to bond the die and the heatspreader. It is an extensive and expensive process to solder a cpu while having good thermal conductivity and preventing damage to the die. The smaller the die is, the higher chance that micro-cracks in the solder will occur, which can kill your cpu. And that's the reason why Intel uses TIM. Not because they're cheap and they want to maximize profits, but because Intel's engineers know this and having a functional CPU long-term is more important than any thermal advantage that soldering has. They could get away with soldering Sandy Bridge because it was on a larger node, but Ivy-Bridge and onwards use pretty small dies, so they couldn't solder them because of the risk of damage.
The reason why Intel doesn't use higher quality TIM like liquid metal is because it isn't necessary. The main reason for the large temperature difference between stock and delidded isn't mainly the TIM, but the sealant they use to stick the heatspreader to the substrate. It increases the distance between the die and the heatspreader, which lowers thermal transfer efficiency. After removing that for the delid, you shorten the distance between the two materials, which improves thermal efficiency. I can't comment on Intel's TIM because I don't know what it's composed of, but considering that most pastes on the market perform within ~5C of each other (more like 2C for the more popular ones), I think it's safe to say that it doesn't have extremely poor thermal conductivity.
And because paste doesn't stick to silicon that well, if it wasn't for the sealant raising the heatspreader away from the CPU, it would get squished out due to the increased pressure and multiple thermal cycles. This is why those who opted for a paste instead of liquid metal are experiencing higher temperatures over time.
Then, you have the manufacturing differences from heatspreader to heatspreader. Some are more convex than others, which will lower thermal transfer efficiency on the edges, and others have minor imperfections on and underneath the surface that TIM will have to compensate for. Some chips also have more leakage than others, so that is also another big contributor from the temperature variances from one CPU to another.
If I'm wrong on anything, please let me know so it can be corrected. I just want to stop the misinformation going around about Intels' TIM
In short, it isn't as easy as just melting on some solder to bond the die and the heatspreader. It is an extensive and expensive process to solder a cpu while having good thermal conductivity and preventing damage to the die. The smaller the die is, the higher chance that micro-cracks in the solder will occur, which can kill your cpu. And that's the reason why Intel uses TIM. Not because they're cheap and they want to maximize profits, but because Intel's engineers know this and having a functional CPU long-term is more important than any thermal advantage that soldering has. They could get away with soldering Sandy Bridge because it was on a larger node, but Ivy-Bridge and onwards use pretty small dies, so they couldn't solder them because of the risk of damage.
The reason why Intel doesn't use higher quality TIM like liquid metal is because it isn't necessary. The main reason for the large temperature difference between stock and delidded isn't mainly the TIM, but the sealant they use to stick the heatspreader to the substrate. It increases the distance between the die and the heatspreader, which lowers thermal transfer efficiency. After removing that for the delid, you shorten the distance between the two materials, which improves thermal efficiency. I can't comment on Intel's TIM because I don't know what it's composed of, but considering that most pastes on the market perform within ~5C of each other (more like 2C for the more popular ones), I think it's safe to say that it doesn't have extremely poor thermal conductivity.
And because paste doesn't stick to silicon that well, if it wasn't for the sealant raising the heatspreader away from the CPU, it would get squished out due to the increased pressure and multiple thermal cycles. This is why those who opted for a paste instead of liquid metal are experiencing higher temperatures over time.
Then, you have the manufacturing differences from heatspreader to heatspreader. Some are more convex than others, which will lower thermal transfer efficiency on the edges, and others have minor imperfections on and underneath the surface that TIM will have to compensate for. Some chips also have more leakage than others, so that is also another big contributor from the temperature variances from one CPU to another.
If I'm wrong on anything, please let me know so it can be corrected. I just want to stop the misinformation going around about Intels' TIM