Chipped Cores

[Indyxc]

Hey Guys,

I've had 2 naked Opterons now, and both have had chipped corners on the core. My first Opteron 148 made it chipped to the 2nd owner, although I never saw it happen.

However, my current Opteron 170 came chipped from the factory! I pulled the IHS off, and before I even ran it IHS-less, I noticed the core was chipped, seen here: (Upper left)

http://img378.imageshack.us/my.php?image=cimg143015ro.jpg

The TIM in the back of the IHS showed the inprint of a chipped corner, so the IHS went on after the core was chipped.

Since then I've managed to develop a small chip in the middle of the side of one of the cores, and I have no idea how. I pulled the cpu out the other day ago, and there it was. I have pads, and don't see how my waterblock could chip it in the middle.

Anyway, this chip is rather golden does 2970 on water. My question is what experience do you guys have with chipped cores? How much does it take to kill the cpu? I mean most of these chips are so small you can barely see them, so it's doubtful the core is so close to the surface, but I'm still wondering.

Thanks

[tsuehpsyde]

Chips on a core are a russian roulette. I've seen the smallest of chips completely kill a processor when it should have been fine, and entire chunks missing and the chip working flawlessly. Basically, if you get a chip, you plug it in and pray. If it test okay, you're good, just be careful with it. ;)

[ahmad]

I mean you have millions and millions of transistors. Its possible that some of the gates are very task specific and maybe only a handful of programs make use of them. For the most part, I doubt that AMD or Intel keep the main logic unit around the edges.

Here is a picture of the wafer:

http://www.hardocp.com/image.html?image=MTExNTM5NzM4MUNQaDljWXlNc1RfMV80X 2wuanBn

So as you can see the chip is either in the l2 cache or in the PU itself. If its the L2 cache you will notice errors all over the place right away (if you run prime95 small FFT for example). But if its the PU, then you will have to run some pretty comprehensive low level program to check every nook and cranny of the CPU...

Also, its possible that you might notice errors in a 64bit environment that werent present in a 32bit one, so thats another way of testing. Just a quick google turned up:

http://www.7byte.com/index.php?page=burnin64

Don't know how good it is, but it says specifically designed for AMD64, so it must be somewhat useful.

[Reznik Akime]

Tried it and I get some kinda access viloation error followed by a failed L1 cache no matter what speed I run my CPU at. Seems a bit buggy.

[CRUSH-ER]

Yep, russian roulette for sure. I had a major chunk taken out of a Duron once and it ran fine, where as another cpu I had (can't recall....maybe a 2100+ XP?) was crapped out with a tiny chip.

[i found nemo]

my clawhammer is chipped, it's fine.

[IvanAndreevich]

Sometimes a small chip you can barely see kills. Sometimes you can have half the hore chipped and it still runs like a champ :D

A64 cores are very brittle

[Eversor]

I think the problem is the depth of the chip.
Back when i used crappy heatsinks with horrible mounting clips, i chiped 3 durons and maybe 2 athlons xp. And some of the durons had MAJOR chips. But they weren't very deep, large, especially in the corners. And they wall worked fine, in fact, one is still working for 2 years almost 24/7.

From what i've seen, the part you're actually chipping is not the core itself but some kind of interface wich is glued to the core. If you look at pieces that come of chipping it's more like graphite.

I've seen someone here in the forum with a mobile 64 wich had the "core" full of cracks in the middle, sides, everywere, and it still worked.

I think when this chipping happens sometimes, it's not just that, but the core, wich supposedly is beneath, gets cracked, smashed, whatever damage you think could happen. and then the cpu dies.

But never, "Oh you may lost some L2 cache!"

Anyway i'm not an expert, may be wrong, just stating what i've seen through some 6 years messing with naked core cpu's.

regards

[periquitos]

believe or not , I have a chipped duron 800 that runs , but display corrupted jpegs (all the other formats is fine) and plays mp3 full of noise (wav's are ok)

[Repoman]

Yeah I'd think the core is a bit smaller than the actual silver part

[tsuehpsyde]

I've seen someone here in the forum with a mobile 64 wich had the "core" full of cracks in the middle, sides, everywere, and it still worked.

That was Eclipse/Ozzimark's. It was rounded, so he lapped it, and it looked like a tic-tac-toe board. :nono: Amazing it still worked (and still does). :eek:

[ozzimark]

I've seen someone here in the forum with a mobile 64 wich had the "core" full of cracks in the middle, sides, everywere, and it still worked.
you mean this guy? it's a 3200+ clawhammer, CAABC 0420TPMW. currently running in a rig behind me with an instance of WoW going as my roommate plays through Molten Core with his guild :D
edit: oh yeah, it's not a mobile.. but i figured that would be obvious from the remnants of the IHS glue, but just in case :p:

[tsuehpsyde]

Origami swan ftw! :banana: :toast: