Hacker News

Using voltage glitching to unleash the A100 in my mining card

42 points by lae 3 hours ago | 15 comments

amelius 2 hours ago

But what if nvidia used those fuses because an A100 had too many fabrication faults so it could only be a cheaper mining card?

(which is the more likely scenario because they can make much more money on enterprise/datacenter products, see DRAM)

the8472 4 minutes ago

[delayed]

stingraycharles 18 minutes ago

Isn’t this how these things are always done? Same with number of cores in a CPU, the higher core and lower core come from the same fabrication process, it’s just that the lower core CPU had more faulty cores that are disabled.

BeeOnRope 11 minutes ago

There's an aspect of that, but the primary reason for differences between various CPUs and GPUs which have the same underlying chip is product segmentation.

mmo93 16 minutes ago

Depends a lot on when its from in the product cycle, the yield at the end of production runs are usually so good that it turns into artificial product segmentation

amelius 16 minutes ago

Yes, that's why I question the approach here.

Testing hardware is a complicated matter (you can do a PhD on the topic), and nvidia probably does a better job at it than a hacker in their basement who thinks they can upgrade their GPU for free.

On the other hand ... perhaps a few bit errors is not a problem for AI workloads ... but they could also crash your system ...

nom 12 minutes ago

it appears the opposite is true and that's why it's faster than an A100, which is optimized for yield and allows more defects

phelix001 15 minutes ago

They definitely did, but maybe you can get some good results running your own tests and determining if they really ARE bad or not, or they just overly tagged them out.

roger_ 27 minutes ago

Glad I jumped on these cards, excited to give this a try!

Hard to believe $1k was a deal a few months ago (and $200 before then).

gravypod 15 minutes ago

I really wish I did. I told a friend about how I bet an unlock would come and decided to buy them when I heard about an unlock.

The highs and lows of my predictive capabilities

roger_ 4 minutes ago

I usually miss out on these things, but I'd been monitoring the eBay prices rising for inferior cards and figured this was a good bet.

Annoying thing is finding a good motherboard to put multiple blower cards in. Mining rigs are a steal but PCIe x1 limitation is annoying. Got a bunch of Volta cards too sitting around until I figure out where to put them (and the performance per watt sucks next to the 170).

SillyUsername 46 minutes ago

I just wish they had something like this for older Tesla p100s, p4s...

Savlume 24 minutes ago

[flagged]

samlinnfer 54 minutes ago

Before you get too excited about the CMP 170HX, the prices had already skyrocketed and that card doesn't a cooler on it and is designed for a server cooler that sounds like a jet engine. Also most of the 80GB vram unlocks have bad RAM and that is the reason they were locked in the first place, otherwise they would have became A100s.

Anyways, that's what I tell myself as I taste my bowl of sour grapes.

whizzter 9 minutes ago

Yeah, cooling AND underclocking will probably be required to somewhat safely operate these.

That said, 80G for something that you picked up for cheap could be an absolute steal these days.

roger_ 48 seconds ago

I sensed the sour grapes :D

Bad RAM isn't a huge issue as you can flag and ignore the relevant regions and be down a few MB.

Kevin_Flynn 5 minutes ago

The ebay auction headlines have already rewritten themselves.