What are the little things on the underside of a CPU?

Dangerous_Dave · 11 Sep 2015 at 10:33

1) As per title - wondering what those small components on the underside of a CPU are and:

2) How important are they for functioning? Would you expect no functioning if some missing, or partial?

NoNameNoNumber · 11 Sep 2015 at 10:35

So you've broken a CPU... Yeah you've broken it.

eddiew · 11 Sep 2015 at 10:45

NoNameNoNumber said:
So you've broken a CPU... Yeah you've broken it.

I think you're onto something there

By and large sensitive electronic gadgets tend to require all of their factory-attached doohickeys in order to... work.

(The most likely thing is that they're capacitors or resistors, but knocking them off will sever a circuit and kill the chip.)

Dangerous_Dave · 11 Sep 2015 at 10:56

Naw somebody sent me one sans stuff on the bottom. Without noticing the missing bits on the bottom, I tested it and it seemed to be working, and ultimately I resold it. Buyer complained that it had bits missing off the bottom - chip comes back and lo and behold it does! BUT it's STILL working!? So now i'm wondering what that stuff actually does.

PhillyDee · 11 Sep 2015 at 11:04

Thing is, has it been knocked off, or is it a soldered pad. It may not have been there to begin with. Not all pads will have components. They mass produce single PCB's, and then use different configurations depending on the actual need.

Deathjester · 11 Sep 2015 at 11:08

I'd suggest you post a picture of what you're talking about.

Dangerous_Dave · 11 Sep 2015 at 11:08

This is original :

This is mine:

Dangerous_Dave · 11 Sep 2015 at 11:09

Not just one or two - more like about 9!

Deathjester · 11 Sep 2015 at 11:10

a) were they there when you sent it
b) are you sure it's the same chip you got back?

Is it going to work?
No probably not.

NoNameNoNumber · 11 Sep 2015 at 11:19

Looks like the buyer has sent you a dud back

Dangerous_Dave · 11 Sep 2015 at 11:33

It does work - at least appears to. Boots windows no problem.

tyler_jrb · 11 Sep 2015 at 11:37

What did they do? Have a few rounds of tennis with it lol. They have been knocked off you can clearly see that due to how the solder is formed.

It might load windows but run prime95 and it will likely fry it, or run slow. Those small parts are ceramic capacitors and are thus to regulate voltage for the cpu core. Without those it ain't going to last long. Especially with 9 of them missing.

Nasher · 11 Sep 2015 at 12:15

Did you note down the serial number of the one you sent? I'm betting they either broke it or are sending back a different one.

PhillyDee · 11 Sep 2015 at 13:08

Deathjester said:
a) were they there when you sent it
b) are you sure it's the same chip you got back?

Is it going to work?
No probably not.

Didn't bother reading the rest of the thread then?

mmj_uk · 15 Sep 2015 at 22:48

They're surface mount resistors, I'd imagine they're quite important can't imagine Intel add them for decoration.

How on earth did so many get knocked off? the CPU might still work but don't be surprised if it's unstable or dies.

BubbySoup · 15 Sep 2015 at 23:18

I had a similar CPU like this I was given by a friend who claimed it didn't work. I plopped it into a system and it worked no problem, in fact it ran 24/7 without a hitch in a little file server streaming the odd film or album every now and again.

However as soon as you booted into a game or ran prime it would crash within a minute. It lasted about 7 months before giving up completely.

esoteric · 16 Sep 2015 at 07:02

My brother knocked off a capacitor on our old Geforce 5950, didn't effect it at all.

Orangey · 16 Sep 2015 at 09:35

Those aren't the same model are they?

Have you bought a Chinese clone??

rtho782 · 16 Sep 2015 at 09:39

Knocked off resistors won't always mean it doesn't work, but will reduce it's stability and longevity.

In the same way as bent/broken LGA pins can be critical and break a motherboard, but can be OK, depending where they fall.