New CPU T7100 Toasted

[portosown362]

About a week and a half ago, I replaced the cpu of my R61 with a T7100 (it originally had a 540). It has been working with the R61 with no problems.

However, today, I began to smell something burning from my R61. Suspecting it may have been the cpu, I opened the R61 and examined the motherboard, especially the cpu. The burning smell came from the CPU. It was not burning, but it was super-hot and looked a bit faded when compared to a few other cpus I have.

I replaced the t7100 with a spare dual-core processor (t2390) and it works with my R61. Due to the burning incident of the t7100, what do you guys think caused this to happen and what precautions would you recommend I take to prevent this from happening again?

Just some notes:

1. I applied a "pea-sized" amount of thermal paste on the t7100 before installation. When installing the t2390, I applied two, pea-sized amounts of thermal paste. Brand is Arctic Silver.

2. I checked other parts of the motherboard and there is no damage whatsoever.

[Cigarguy]

Only thing I can think of that would cause that is improper installation of heatsink fan. Surprise the T7100 got to the point of "toasty", normally the system would become unstable and crash way before then. Modern CPUs are designed protect themselves against death by throttling down first then shutting down before becoming toast. Having said that a T7100 is no big loss being that it is the lowest of the Merom series. A T7300 will be an improvement and TuuS sells them for super cheap. Of course a T8300 or T9300 is much nicer.....assuming it's not destined for the toaster.

[RealBlackStuff]

You'll kill a CPU with so much thermal paste!
Remove the fan again and clean everything up, using e.g. Isopropyl alcohol.
Then apply only a rice corn size amount of AS5 on the CPU, and spread that evenly with e.g. a credit card.
For full instructions, see this PDF: http://www.arcticsilver.com/pdf/appmeth ... d_v1.1.pdf

[Cigarguy]

^^^ yes less is more. Also make sure the heatsink fan is not bent out of shape and tighten down properly. A couple of T61 with good specs came to me for $40 because it "is not working" due to either dried up thermal paste or loose screws securing the heatsink.

[portosown362]

I think you guys are right. In regards to the thermal paste - I most likely put too much. Plus, I handled the cpu (t7100) using my barehands and when cleaning it, I removed the thermal paste off by simply using a paper towel.

Now, with the advice you guys provided, I reinstalled the cpu (t2390). Instead of using my barehands, I put on latex gloves to handle the cpu, and when cleaning it, I used alcohol and wiped it clean. When reapplying the thermal paste, I put a far lesser amount of thermal paste (rice, corn-sized as RealBlackStuff recommended). I then spread it out evenly using a plastic knife, reinstalled the cpu and reassembled the laptop.

Right now, the cpu seems to be working fine, but I will most likely be able to see if any cpu heating problems occur in roughly 1-2 weeks.

Also, Cigarguy's comment on the cpu becoming unstable and crashing might explain why my computer began to slow down a little bit over the last few days.

Thank you again for your help! If any problems arise, I'll keep you guys updated.

[Cigarguy]

No need for gloves, there's nothing unholy that you can catch from the CPU.

When taking off TIM, I start by getting the worse of it with a Kleenex dipped in rubbing alcohol. When the major of the goop is off, I'll use a lens cleaning cloth dip (damp not dripping wet) in rubbing alcohol to polish it off. Then let it dry for a minute or two while I do the same thing to the surface of the heatsink fan that sits on top of the CPU, chipset, GPU, etc. Once everything have a minute or so to dry off, I take compress air and blow over the surface to remove any dust particle or lint from the cleaning. Then I'll apply fresh thermal paste and install the heatsink fan. Dust or lint from cleaning stuck between CPU and heatsink is not a good thing. Make sure you tighten the screws as tight as it'll go without stripping it.

For my own personal reference, I use HWMonitor to see the temps before and after. If you want to stress test the CPU, a favourite amongst overclockers, is Prime95.

[portosown362]

No need for gloves, there's nothing unholy that you can catch from the CPU.

The unholy spirit that burned my poor t7100 might come to burn me too! But I remember reading on the manual (which RealBlackStuff kindly provided) about the oils on our hands going on the cpu and possibly doing damage.

But thanks for sharing on what you do when installing a cpu - I will add your excellent tips to my next cpu installation!

[Cigarguy]

The T7100 is really a crappy entry level CPU. If you are going through with all the trouble, at the minimum, upgrade to a T7300 for cheap from TuuS. If you want a really nice upgrade look for a T8300 or T9300.

When cleaning, wrap the alcohol damp tissue or lint free cloth around your finger. That way you will not get any oily human DNA on it.

[portosown362]

The T7100 might be an entry-level cpu, but it's a cheap experiment. I eventually will install something around the realms of a t7300-t7500 once I know for sure the cpu won't burn again.

Forgive me if my questions sound elementary on cpus, but when I opened my laptop to install the replacement, I noticed that there was a wording on where the cpu is placed reading,"BGA479". What does this mean exactly? Would this be called the socket? If this helps, I believe the cpu that came with the laptop (celeron 540) has a socket p. I should add that the t7100 (that burned) also has a socket p.

[Cigarguy]

Yeah basically it's just the socket type, your Thinkpad will also take a socket P processor too.

Here's a little more info on it.

http://en.wikipedia.org/wiki/Intel_Core ... tecture%29

[portosown362]

Awesome link - thanks! Pretty amazing to see the large family line of cpus available!