How do you detect a falsely re-lidded CPU?

[Quartz-1]

Thanks to delidding tools, it's now possible to put the lid of - for example - an i7 CPU on an i3 CPU. Or - more subtly - the lid of an i5-2500k on an i5-2500. Can this be casually detected?

 

[BinarySynapse]

There's a 2D barcode on the substrate that you can scan using an app to get the ATPO number. Then go Intel's warranty check page enter the FPO number from the lid and the decoded ATPO number to see if pair can be found in their database.

 

[Quartz-1]

So, not a casual check. I was hoping for something to be printed along the edge or underside or something.

 

[BinarySynapse]

If you want to check it before you buy it, you can scan the barcode from a picture of the CPU, but there's nothing else to indicate that the lid and the CPU under it match up.

 

[Deleted member 88227]

Damn, I never even thought that this could even be an issue. Now I'm gonna be skeptical about buying used CPUs.

 

[janas19]

Damn, I never even thought that this could even be an issue. Now I'm gonna be skeptical about buying used CPUs.

Yeah, but even then I doubt this affects the type of person who posts on this forum. I mean if you are buying through Amazon or eBay you are protected. And on Craigslist or online classifieds, you would be pretty stupid to buy from a first time seller or meet someone in a public place to buy a bare chip CPU. Scammers target naive and unsophisticated buyers not people who do their homework first.

 

[Chapeau]

You could always just look at the way the IHS is mounted to the PCB. The stock chips have a distinctive black sealant (glue) that squishes out at the edges.

The rough texture and amount of glue is a giveaway on this factory example.

This is typical of a DIY job. No excess glue...
- The glue is also very smooth like most consumer sealants, silicone's and adhesives.