Laptop RTX 3070 GPU spotted inside a desktop graphics card, and of course it's for mining crypto

Here's a curious case of a GPU switcheroo. There are RTX 3070 graphics cards up for sale in Asia with mobile RTX 3070 chips in them—the kind intended for gaming laptops, not discrete graphics cards. Well, it could be someone who had an abundance of laptop GPUs to hand and no laptops to put them in, but of course, it actually appears a play to bypass any cryptocurrency mining restrictions and make more money.

A Facebook post from Vietnam, spotted by leaker I_Leak_VN, outlines someone's hands-on impressions of the so-called RTX 3070M. They mention that "this GPU was previously only used for laptops, now they have packed it into cheap VGA." There's no clear branding visible on the shroud. However, it's likely manufactured by a GPU OEM partner in China as it's also been spotted on the Chinese marketplace Taobao and Aliexpress.

The RTX 3070M is going for the equivalent of $738 on Aliexpress. That's not particularly cheap—you could pick up an RTX 3070 for less on Newegg today—but there's another draw for this card's most likely customers: cryptocurrency mining efficiency.

A regular RTX 3070 will operate at around 45MH/s when mining ethereum, and that's a reduced rate due to Nvidia's cryptocurrency mining limiter, Lite Hash Rate (LHR), which prevents many of its discrete graphics cards from running at 100% efficiency when a specific mining workload is recognised.

This mobile RTX 3070M is reportedly able to deliver around 65MH/s, using a GPU that was never thought to be much use to miners and therefore never came with any form of crypto-mining limiter installed. 

From what I can tell, 65MH/s is the RTX 3070M's ethereum hash rate and not a hybrid rate of multiple hashes at once. Either way, it's reportedly higher than what an LHR RTX 3070 desktop card is able to deliver out of the box. 

Though it must be said that Nvidia's LHR lock has been repeatedly broken or severely reduced over the course of the past year, and many miners had already considered Nvidia's actions to be largely redundant in heading off mining demand for gaming GPUs. 

There is also a catch for the RTX 3070M: as listed on the Aliexpress product page, the RTX 3070M will not work with Windows 10, which is almost certainly down to desktop driver issues. Instead, it requires Linux. That's all fine and dandy for crypto-miners that already use Linux for their mining rigs, but it does slam the door on a regular gaming PC running Windows with one of these cards installed.

So if you still thought these were in any way intended for gaming purposes, you'd be sorely mistaken.

The profitability of ethereum has slipped in recent months, however, alongside a larger crypto crash that has seen most of its gains this year wiped off. That has seen GPU demand falter for the first time in at least 18 months. While graphics cards are still too expensive, they are at least now widely available to purchase—the RTX 3070M desktop GPU may be arriving a bit late to the party.