Contact pads on Intel CPUs - front side

[Sheep221]

Since introduction of the first i7, every Intel CPU since then carries gold contact pads also on the front side randomly placed around the IHS, I never found out what is their purpose. Any ideas? Googling didn't reveal anything.

Mobile CPUs have them as well:

 

[Wall Street]

I believe that they are debug test pins which I would assume are used in the validation & binning processes.

 

[VirtualLarry]

Yeah, they're for packaging and test, validation, debugging, and probably micro-code programming.

 

[hojnikb]

Yeah, they're for packaging and test, validation, debugging, and probably micro-code programming.

I'm pretty sure there is no microcode, as that gets loaded first thing via bios.

 

[pcgeek11]

If I remember correctly there was a time when you could use conductive ink to connect some of those to unlock a processor at least on AMD Processors.

 

[VirtualLarry]

I'm pretty sure there is no microcode, as that gets loaded first thing via bios.

Uhh, the CPU has to have a built-in default microcode, otherwise it wouldn't boot the BIOS.

The BIOS can load subsequent microcode patches into microcode SRAM, but the CPU needs a stock microcode to boot, AFAIK.

 

[Sheep221]

Uhh, the CPU has to have a built-in default microcode, otherwise it wouldn't boot the BIOS.

The BIOS can load subsequent microcode patches into microcode SRAM, but the CPU needs a stock microcode to boot, AFAIK.

This is correct, but instruction sets and so on I know are hardwired in the silicon.
I thought it has something to do with post manufacture configuration but wanted to know more details. As from the pics above every socket has them placed in different pattern.
can't check electrical behavior manually because socket and cooler block them.
Maybe Dresdenboy will know.