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Input:
Question: What is the best  for 4770K DELID ?  Liquid Ultra or PRO ?
Document: The max temp now was 47c which is an 11c drop. The only thing I have to say negatively about the Liquid PRO is, it is more difficult to start spreading out initially, but then it is a piece of cake once it adheres to the CPU/GPU. I have always used the pea size method in the center of the CPU/GPU and let the cooler spread out the paste. However, Liquid PRO MUST be spread out with a q-tip.
This has now become my favorite thermal paste. I de-lidded my Intel i7-3770k processor and replaced the horrible OEM thermal paste under the IHS with Liquid PRO. I also replaced the Phanteks nano particle paste between my CPU and Heatsink that came with my Phanteks PH-TC14PE twin tower with the Coollaboratory Liquid PRO. The de-lidding procedure and the use of Coollaboratory Liquid PRO drop my temp 30c.
After de-lidding and using Coollaboratory Liquid PRO, the max temp now is 66c at 4.8GHz. I honestly can't say the Liquid PRO alone drop temps 30c, but it did have a part in the huge drop, so to be fair and compare apples to apples, I changed the thermal paste on my liquied cooled GPU, using the same Phanteks nano particle paste on my GPU, I stressed the GPU to a 100% load with Furmark for 10 mins.
As part of a demonstration rig for the Intel Colorado LANFest 2013, I tried all of the top-rated thermal interface materials on a direct-die attach 4770K and Liquid Pro took top place by about 3 celsius cooler than the next runner up which was IC Diamond 24K.
Best stuff on the market. I've used them all and Coollaboratory Pro blows everything away. Fairly difficult to apply and don't get any on the motherboard.
While it still works best, the relative improvement is not as good with other applications, and might not be worth the risk. But for cpu delidding it's awesome. It's basically doubled my oc over stock,. But If you delid, be careful, and don't hate me if you bust your chip.
pros : Performance of this product is great. I overclocked my i7-4770K to 4.6Ghz, When I applied this thermal grease to CPU, the temperature of CPU was dropped over 25&#8451;.cons : When apply this thermal grease to surface of CPU, thin spreading is very hard.
I'm running a 4770K over clocked at 4.2GHz with an H100 Corsair hybrid water cooler. My CPU temps are ~35C or less at idle, and peak at 60C under full load during stress tests (10-15C cooler than a friends nearly identical system using a paste TIM).
I purchased this product about 6 months ago, I used this on many different desktops platforms and ordinary laptops. Many people buy this to put it between the processor die and IHS. But even just putting it on IHS alone can drop temperature by 5~8 degrees on soldered CPUs like nehalem and sandy bridge, the difference is going to be much greater. I must say, this is The best thermal compound product out there.
Dropped my temps 5-10 degrees Celsius. Pretty amazing how it does that. Was getting 35-58c on stock. 24-52c on mx4 and 19-42c on Liquid pro.
Answer: Neither.  These are metallic and therefore able to transfer electricity extremely easily.  I would not suggest using any metallic-based solution for cooling a de-lid unless you have enough money put back for another processor should the first attempt at applying this liquid not go according to plan.  Think near-mercury consistency.  However, this being said, PRO has a slight lead over the Ultra, due to significant higher level of thermal conductivity.  If you're de-lidding you're looking for greatest performance gain, PRO is the better choice for this.  Best solution would be to use PRO and a good closed-loop liquid cooling system without de-lidding.