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This Mobile Comet Lake CPU Can Be Installed Into LGA 1151 Desktop Motherboards

Intel QTJ2 Mobile With Interposer
(Image credit: AliExpress)

Someone on AliExpress is selling a rather unique processor you won't find anywhere else: a Comet Lake mobile processor with a built-in interposer that allows support for LGA 1151 desktop motherboards. If you want to run an efficient 10th Gen mobile CPU on your desktop, now is your chance!

The processor itself is listed as QTJ2, and is a hyperthreaded Hexa-core chip with a base frequency of 2.4GHz and a boost clock of 4.3GHz. We aren't sure exactly what it is, but it appears to be a production sample that never got produced. The QTJ2 mostly resembles an underclocked Core i7-10750H, for comparison. 

The chip is no slouch when it comes to performance, mostly resembling gaming performance to that of a Core i7-8700K from a few years ago. One YouTuber tested the chip out and it had no problems handling a GTX 1080 in Shadow of The Tomb Raider.

Unfortunately, compatibility with this chip is not as straightforward as we would like it to be. Due to the QTJ2's mobile nature, the chip isn't compatible with LGA 1151 motherboards without a BIOS modification. Luckily, the seller of the chip will happily take in your motherboard's BIOS and customize it for you, so the mobile Comet Lake chip can support your board.

There are other limitations worth mentioning. For cooling, you have to ensure the CPU cooler you use has a flat surface. This means coolers with heat pipes that directly contact the CPU are not an option (like the Hyper 212 EVO), because the QTJ2 CPU does not have an IHS. You need a cooler with a perfectly even surface to ensure the die is cooled properly.

Another issue is chipset limitations. For some reason, the Comet Lake chip can only be supported on select 100 series,  200 series, and 300 series boards (for example Z390 is not supported). So be sure your chipset can support the chip before you make your purchase.

Still, it's cool to see a mobile Comet Lake chip working on a desktop computer. Ironically, this is the ONLY way to get a proper Intel 10nm based chip inside a desktop at this current time. 

Desktop variants of Comet Lake and upcoming Rocket Lake chips are still running on Intel's older 14nm process. So if you're desperate to get 10nm working on desktops right now, this is your only option. Just beware this configuration is officially unsupported by Intel and is only supported by third parties, so make sure you know what you're getting into.

  • ThePhillipster
    I might be wrong, but I'm fairly certain that 10th Gen Mobile had both 10nm and 14nm parts. The 10nm parts were known as Ice Lake, and only went up to 4c/8t. Comet Lake mobile (10th gen 14nm mobile) went up to the 10980HK and was/is found in high performance gaming laptops. Since the CPU in this article is a six-core CPU, it would be incredibly unlikely that this seller gained access to an engineering sample six core 10nm Intel processor.
    Reply
  • Potty Point
    ThePhillipster said:
    I might be wrong, but I'm fairly certain that 10th Gen Mobile had both 10nm and 14nm parts. The 10nm parts were known as Ice Lake, and only went up to 4c/8t. Comet Lake mobile (10th gen 14nm mobile) went up to the 10980HK and was/is found in high performance gaming laptops. Since the CPU in this article is a six-core CPU, it would be incredibly unlikely that this seller gained access to an engineering sample six core 10nm Intel processor.
    Yes agree. the Core i7-10750H is a 14nm processor. Maybe intel did try to make 10nm 6 core processors and this is an engineering sample of the failed attampt... but yes extremely unlikely.
    Reply
  • Valantar
    Potty Point said:
    Yes agree. the Core i7-10750H is a 14nm processor. Maybe intel did try to make 10nm 6 core processors and this is an engineering sample of the failed attampt... but yes extremely unlikely.
    Intel's first 10nm >4-core CPUs are the upcoming Tiger Lake H, in the mobile 11-series. Any engineering samples would still be Tiger Lake - porting a design to a new node is a multi-million dollar undertaking requiring a large team and months of work, so there's no chance whatsoever they've just thrown together some 10nm Comet Lake samples just to see if they worked. And samples that early would be anything but trivial to get to work on an older motherboard (and likely wouldn't be stable at all).

    This is bog-standard Comet Lake-H silicon, which is the exact same as the desktop Comet Lake-S silicon, just binned and packaged differently. We've seen repackaging of mobile chips like this in previous generations too - seems like a sensible, if weird, way to reuse functional silicon that would otherwise end up in a landfill.
    Reply
  • TechSmack
    Here is the comment you'll never find on any website about these processors.

    I have bought this processor to test the "performance" it gives. Trust me it's nowhere near a real i7 8700K. First of all mounting the IC on the heatsink is a complicated process. Next comes the first boot and hopes it "all works". Even if it does boot the next step is overclocking the processor, because in stock mode it runs like i3 8100. Once the overclock is over and everything is fine and stable, the benchmark tests result in 101% i7 8700k scores you're then ready to fire up some games and play smooth, right? No, the issue lies in the following trick that no one has ever told. You won't get the FPS of a real i7 8700K in any game, and that's because the chip is not supposed to work with a normal desktop. It is meant for engineering the CPU. While the benchmarks of the CPU, yes, they do tell us we have i7 8700K, fine. What they don't tell us is how fast the CPU is with the peripherals, and well as you guessed, a game requires a good CPU as much as a good GPU. The GPU might be 3090, and the CPU 8700K, but the connection between will be PCIE 2.0 16X. But hey, after all it just lowers 1% of the FPS, so who cares right? Well, not quite. Even though we can change the pcie gen to 3.0 in BIOS, we will still suffer bottlenecks, not because of the lanes or PCIE gen or CPU or GPU clocks, but because of the way PCIE is implemented in the CPU and that is implemented for Engineering purposes, meaning it's first purpose is to function, but it's function is not optimized. Changing the physical implementation is not possible. Also I would like to add some SSD stutters and high access times. Plugging an USB 3.0, well just forget about seamless folder browsing. The transfer speeds are there, but the access times are hell.
    In my opinion, it's just better to stick with an official sample of an Intel CPU rather than engineering sample. For some bucks more you'll be saved from the extra headaches this engineering sample will give to you. Trust me it's not worth the money, for the extra headaches it makes.

    Ah, and I forgot to mention the occasional system crashes.
    Reply