Soldered vs Unsoldered CPU?

[IAEInferno]

Searched google but came up with other results.

 

Just wanted to know the pros and cons of a soldered and unsoldered CPU?

[Simon771]

When CPU die is soldered to IHS, it will provide better thermals. Because it's touching directly, and more heat can be dissapeated or something like this.

When CPU is not soldered (using TIM), there is worse cooling performance. It just can't cool that good.

 

I know for fact that i5 2500 CPU is soldered, same for K version.

And all 2011 socket CPUs are also soldered to give better cooling performance.

 

My i7 4790k is not soldered, and that's why I get up to 80°C on custom water cooling with mild OC.

Meanwhile, i7 6800k is soldered and would have around 20°C lower temps.

[SLAYR]

8 minutes ago, IAEInferno said:

Searched google but came up with other results.

Do you mean a BGA (ball grid array) chip vs a "unsoldered" PGA, or LGA cpu. Basically how the cpu attches to the motherboard?

 

Is there an actual question?

[IAEInferno]

Just now, SLAYR said:

Do you mean a BGA (ball grid array) chip vs a "unsoldered" PGA, or LGA cpu. Basically how the cpu attches to the motherboard?

 

Is there an actual question?

 

 

Pros and cons...

[APasz]

A soldered cpu can also mean it's soldered to the mobo rather then socketed. So what exactly do you mean?

[IAEInferno]

Just now, APasz said:

A soldered cpu can also mean it's soldered to the mobo rather then socketed. So what exactly do you mean?

edited question.

[APasz]

7 minutes ago, IAEInferno said:

edited question.

In the context of soldered to mobo vs socketed. Nothing other then space efficiency and being able to upgrade a socketed cpu.

in context of a soldered IHS vs a TIM IHS. Soldered offers better heat transfer from die to IHS as it's metal to metal contact. Using a tim is easier to use and replace but has lower thermal transfer capacity.

[Space Reptile]

21 minutes ago, APasz said:

. Soldered offers better heat transfer from die to IHS as it's metal to metal contact. Using a tim is easier to use and replace but has lower thermal transfer capacity.

soldered tim is always better ,

consider how many people actually delid there cpus , id rather have em all soldered

[zMeul]

6 minutes ago, Space Reptile said:

consider how many people actually delid there cpus , id rather have em all soldered

as die surface increases, CPUs can no longer be soldered to the IHS

as the solder cools down it also shrinks in volume quite a bit and that shift will also tear the layers of the die

[APasz]

4 minutes ago, Space Reptile said:

soldered tim is always better ,

consider how many people actually delid there cpus , id rather have em all soldered

TIM is not solder and solder is not TIM. Solder is mostly tin alloys wheres TIM's are made of plastics and ceramics, sometimes metal is added to it in the case of arctic silver.

Please do not get the two mixed up.

[zMeul]

6 minutes ago, APasz said:

TIM is not solder and solder is not TIM. Solder is mostly tin alloys wheres TIM's are made of plastics and ceramics, sometimes metal is added to it in the case of arctic silver.

Please do not get the two mixed up.

TIM stands for Thermal Interface Material

no where does it say that solder can't act like TIM - solder does act exactly as thermal transfer material between the CPU die and the IHS, that's why it's there

[-rascal-]

30 minutes ago, zMeul said:

as die surface increases, CPUs can no longer be soldered to the IHS

as the solder cools down it also shrinks in volume quite a bit and that shift will also tear the layers of the die

@zMeul is absolutely correct.

 

Here is an article from November 2015 that explains it very well.

http://overclocking.guide/the-truth-about-cpu-soldering/

 

Quote

Keep in mind that you also have to glue the IHS to the PCB during the soldering process. Solidifying indium will shrink during the soldering process. As a result, DIE and heatspreader will be pulled together. The result is an uneven heatspreader which you might have read about before.
...
...
The micro cracks will also decrease the thermal conductivity but will especially increase the thermal resistance at the corner of the DIE. Without the gold layer between diffusion barrier and solder preform, delamination of the solder preform would occur after few thermal cycles. 
...
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Void and micro crack occurrence is mainly affected by the solder area – thus the DIE size. Small DIE size (below 130 mm²) e. g. Skylake will facilitate the void occurrence significantly. However, CPUs with a medium to large DIE size (above 270 mm²) e. g. Haswell-E show no significant increase of micro cracking during thermal cycling (Figure 12). This failure mechanism is one reason why small DIE CPUs like Haswell-DT or Skylake are not soldered while the large Haswell-EP CPUs are soldered.
...
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Whenever I read sentences like “What a ripoff – Intel doesn’t even solder a 300 USD CPU” or “Why does intel save 2 USD on soldering” I’m thinking
Stop hating on Intel. Intel has some of the best engineers in the world when it comes to metallurgy. They know exactly what they are doing and the reason for conventional thermal paste in recent desktop CPUs is not as simple as it seems.

 

[APasz]

32 minutes ago, zMeul said:

TIM stands for Thermal Interface Material

no where does it say that solder can't act like TIM - solder does act exactly as thermal transfer material between the CPU die and the IHS, that's why it's there

I'm saying that the terms are not interchangeable. If you go by the dictionary definition of what TIM is then almost everything is or can be a tim but of course this isn't right.

TIM is a specific thing, normally made from ceramics and/or plastics, sometimes metals such as tin or silver or other minerals like diamond are added.

Most solder is a tin alloy, no plastic, no ceramics, no diamond.

There is a difference between them. Yes they ultimately they do the same job, balance heat between 2 surfaces but they do it in different ways.

 

If you don't understand this basic difference, what are you doing in IT?

I hope you understand. The IT industry is full of minor differences like this.

[Lays]

1 hour ago, Simon771 said:

When CPU die is soldered to IHS, it will provide better thermals. Because it's touching directly, and more heat can be dissapeated or something like this.

When CPU is not soldered (using TIM), there is worse cooling performance. It just can't cool that good.

 

I know for fact that i5 2500 CPU is soldered, same for K version.

And all 2011 socket CPUs are also soldered to give better cooling performance.

 

My i7 4790k is not soldered, and that's why I get up to 80°C on custom water cooling with mild OC.

Meanwhile, i7 6800k is soldered and would have around 20°C lower temps.

The other big part of the temps on haswell is because of the VRM next to the CPU, also x99 cpus generally run lower temps because they have more surface area to dissipate heat.