Delidding disaster

[bryanl]

Digital chips consume almost all their power in brief bursts during clock transitions, which cause voltage overshoots and undershoots that can be great enough to electrically damage the chips.

A 10-watt soldering iron can attach a new capacitor array, after the old solder is cleaned off using rosin flux and very fine desoldering braid. A heat gun at its lower temperature setting will also work for soldering, but cover the other components with 2 layers of aluminum foil.

 

[Vinwiesel]

As others have said, those are just decoupling capacitors, and (assuming you didn't damage the circuit board) it will work fine without one of them. I wouldn't try to reattach it because it is obviously chipped, and it could short out. I've seen chipped ceramic capacitors short before (often after hours of use) and the results aren't pretty.

If you do anything, I would try to remove as much of the remains as you can to avoid any chances of a short. If you're good with a soldering iron, I would remove what's left of the cap and then clean the pads with solder wick. If you're not, then leave it alone.

Exactly this. Damaged ceramic capacitors are just a short waiting to happen. Internally, they are just thin layers of conductive material separated by a very thin insulating layer of ceramic. Once the ceramic cracks, the layers can short together.

Just leave it off. I would guess a 90% chance of this making no difference whatsoever, and a 10% chance of reduced OC ability.

 

[BonzaiDuck]

As others have said, those are just decoupling capacitors, and (assuming you didn't damage the circuit board) it will work fine without one of them. I wouldn't try to reattach it because it is obviously chipped, and it could short out. I've seen chipped ceramic capacitors short before (often after hours of use) and the results aren't pretty.

If you do anything, I would try to remove as much of the remains as you can to avoid any chances of a short. If you're good with a soldering iron, I would remove what's left of the cap and then clean the pads with solder wick. If you're not, then leave it alone.

The repair suggestions are way out of my ball-park, and I wouldn't be happy with the CPU just for leaving it unrepaired. But it's great to know the processor can still function . . .

 

[Vinwiesel]

Just noticed the capacitor below the missing one is damaged too. May want to pop it off as well so it doesn't short.

 

[lakedude]

I like the integrated heat spreaders. Those naked flip chips or whatever they were made me nervous.

I understand direct contact makes for better thermal transfer but I like the extra mechanical protection provided by the IHS.

Now if they invented a sturdier mount that made sure the heat sink went on perfectly level I'd be a fan of the naked chips...

 

[Soulkeeper]

Ok, I just ordered a bunch of stuff off digi-key to fix it (more $ than the CPU costs)
This should be fun 🙂

 

[antisocialmunky]

http://hardforum.com/showthread.php?t=1421792&highlight=oven&page=71 🙂

 

[SunRe]

Don't discourage, that's an easy fix with a 15-25w soldering iron with a good tip (not necessarily very small, it's important to make the heat transfer). A hot air soldering station would be perfect for this but a good soldering iron will do just fine.

Use plenty of soldering flux and you should be fine. If you don't wanna do it, any decent diy'er or electronist will be able to solder those.

Don't think of using the CPU without the caps, at those speeds their function is important, it's not that you won't be able to overclock it but probably it will be very unstable.

 

[Soulkeeper]

I got all the tools/materials to repair it

my eyes just couldn't handle it and everything was too damn small
I ended up losing my temper and stabbing the cpu to death with the soldering iron

way too small to solder, even if I did solder it I wouldn't be able to see if the leads were cross soldered or if a trace was cut/melted.

 

[Vinwiesel]

Thanks for letting us know how it turned out. My technique for soldering those cap packs is:
1: Use solder wick to clean off all the old solder
2: Apply a dab of fresh solder to one pad on the board
3: Attach cap pack to the same one pad that has solder
4: Solder all 4 leads at once on the opposite side (takes practice to do this without bridging)
5: Solder all 4 leads at once on the first side.

This method works well for old tin/lead solder with rosin flux. If you use the right amount and right type of solder, it will stick to the cap and the board, and not bridge in between. Best results with a metcal 144 tip. It is possible to do one lead at a time, it can just be difficult sometimes to get enough contact to the tiny ground pads to get them to wet. Hitting all pads at once delivers more heat, and makes for easier wetting.

Also, I'm reminded of Joe Dirt: http://www.youtube.com/watch?v=YmMRaUX-QSM

 

[Idontcare]

I ended up losing my temper and stabbing the cpu to death with the soldering iron

Sorry to hear this, seems a bit extreme though, no?

I thought you were going to give the "conductive-epoxy applied w/toothpick" a shot? What made you steer away from that option?

 

[Soulkeeper]

Thanks for all the comments everyone 🙂

I went ahead and purchased another 3870, delidded and am running it now.
I got another one on the way, gonna delid it too.

Surprisingly the overclocking is nearly identical even tho the year/week numbers are nearly 1yr apart. I did notice that setting "normal" for the voltages results in lower cpu and nb voltage with the newer one. Maybe AMD is more confident with their yeilds now.