Laptop is fried, trying to determine if it's the MOBO or CPU. And if upgrading the CPU a good idea.

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I have a Lenovo Laptop IdeaPad G780, and I really like this laptop despite how old it is. Specifically it's this model:

https://www.newegg.com/matte-imr-me...inment/p/N82E16834310628?Item=N82E16834310628

That's even the link I bought it from years ago.

Issue is... it's dead. I accidently fried it while I was trying to repair cracking hinges. After doing the repair and testing to see if it worked, it was powering on fine, but I realized I had forgotten to plug in the RAM. So I powered it off (or I thought) and unplugged the AC adapter. Problem was, it had not actually fully turned off, and the normally 100% dead and shot battery I had forgotten to unplug decided to live that one time just long enough to keep the system powered on as I installed the RAM module.

The system just flashes a white screen now and has a burning smell if I attempt to power it on. It's clearly fried, but I don't know where or what component. This was a while ago, and since it's just taking up space I decided to check eBay to see if anyone would buy it for parts even though I REALLY don't want to give it up, and that's when I noticed that I could get a replacement motherboard for this exact model for about $60-70.

What also caught my eye is that none of them had a CPU, instead there is a socket. I had no idea my laptop's CPU was socketed, those are extremely uncommon.

Now though it makes me wonder what component could have fried. If it was something on the motherboard, or possibly the CPU itself since IIRC they started putting the memory controllers on the CPUs long before this laptop was made.

Is there any way I can really find out if I don't have a donor board I can test the CPU in? Would it even be a good idea to test the CPU that may or may not be fried in another board or could I risk frying that board too if it's the CPU?

That's also what got me wondering, since the CPU is socket, this means I might be able to upgrade it too and avoid that problem alltogether. I checked the list of CPUS within that generation here: https://en.wikipedia.org/wiki/List_...y_Bridge_microarchitecture_(3rd_generation)_2

And one issue that I noticed is that my CPU, the i7-3632QM, is a low-power variant with a TDP of 35W. The others have a TDP of 45W or 55W.

Now, I am not going to plonk down $150+ for some extreme edition Core i7-3940XM, but would I risk my laptop's cooling system not being enough for even the 45TDP ones over the 35TDP CPU I have? I was thinking something like an Core i7-3720QM or Core i7-3740QM as those are around the $50-ish range on eBay. The original CPU it came with also seems to go for around $20 on eBay.

And even if the cooling is enough, is there a chance the laptop's motherboard won't accept any CPU other than the one it came with? Or were all these standard enough that if the Laptop's motherboard is socketed, then it should accept the CPUs in that generation with that socket?
 

travm

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Most likely the motherboard. Likely not worth the effort. Cpu may even be soldered on.
 
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Pull the drive and and migrate to a non cracking newer model

If I could buy a new laptop I would instead of trying to go the $60-100 route to fix this one, especially since most new laptops don't have easily removable drives and batteries anymore, or a second SATA port.
 

travm

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If I could buy a new laptop I would instead of trying to go the $60-100 route to fix this one, especially since most new laptops don't have easily removable drives and batteries anymore, or a second SATA port.
You think there is a $60-100 route here?
Laptops are only fixable ish, and doubtful a motherboard would be that inexpensive.
 
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You think there is a $60-100 route here?
Laptops are only fixable ish, and doubtful a motherboard would be that inexpensive.

As I mentioned, I can see multiple motherboards for this laptop on eBay right now for $60-70, and the CPU is $20, around $50-60 if I want to upgrade the CPU.
 
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Limp Gawd
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That's a nice old machine, from the era when laptops were actually made to repaired and upgraded! I'd fix that machine and keep it around if I had it. Only bummer is that Fermi based GT635, almost might be better off disabling that if possible and just using the Intel HD4000 integrated at this point.

I just resurrected a Latitude E5530 that was given to me with soda spill damage. Cost me 55 bucks for a motherboard, an i5 3340M (has faster 1250MHz HD4000 integrated GPU frequency), an extra 4GB of memory, and a new 240GB SSD. A little cleaning of all the base parts to get the sticky residue off, and careful reassembly and I have a laptop that runs Windows 10 LTSC like a champ. It also runs older games decently, been playing some Half Life 2 on mine for fun. There is certainly nothing wrong with a mobile Ivy Bridge for web surfing and other light loads today.
 
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That's a nice old machine, from the era when laptops were actually made to repaired and upgraded! I'd fix that machine and keep it around if I had it.

Yeah, that's a major reason I want to fix it. Modern laptops might as well be fancy tablets are this point.
 

duronboy

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...has a burning smell if I attempt to power it on. It's clearly fried, but I don't know where or what component. Is there any way I can really find out if I don't have a donor board
If you have a thermal camera module for your phone, it's easy. If not, try to narrow it down to areas you suspect. Put some alcohol on chips you think might be getting hot. Fast evaporation means heat. Instant evaporation means very hot.

And one issue that I noticed is that my CPU, the i7-3632QM, is a low-power variant with a TDP of 35W. The others have a TDP of 45W or 55W. would I risk my laptop's cooling system not being enough for even the 45TDP ones over the 35TDP CPU I have?
It's a consideration, for sure. If you're running too hot you can choose some vague CPU power limits for both battery and AC power profiles in windows.

Run a search for Power Options, open it up, select Change plan settings

Click on "Change advanced power settings"

Expand Processor power management

Expand Maximum processor state

Choose a percentage that suits your needs. I have mine at 91% and that keeps temps out of the 80s with no external fans. It's important to note that this is changing a multiplier and there are way less than 100 of them. On mine, anything higher than 91 it's not actually lowering from stock. I think there's one more notch between 91 and 75. It's handy to have Open Hardware Monitor to observe clockspeed to see at which percentage points the system actually changes speeds.


is there a chance the laptop's motherboard won't accept any CPU other than the one it came with?
There is, but I don't have enough experience to say what your chances are. I do know there are socket versions within socket versions and some sites distinguish between them and others do not.
 

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I'd also suggest searching https://forum.thinkpads.com/ and see if anyone has posted CPU upgrade info for your machine. From my experiences the 45W TDP real quad core mobile Ivy Bridge i7s went in machines with upgraded cooling systems like Dell Precisions/etc. Not sure I'd recommend a 45W TDP CPU in your system, how about the 2.9GHz (3.7GHz turbo) 2 core/4 thread i7-3520M instead? If you don't need all the threads, this may be a better option and stays within the TDP? The better single thread performance would benefit web surfing and light usage better then your slower speed quad core.......
 

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It's a consideration, for sure. If you're running too hot you can choose some vague CPU power limits for both battery and AC power profiles in windows.

Run a search for Power Options, open it up, select Change plan settings

Click on "Change advanced power settings"

Expand Processor power management

Expand Maximum processor state
I like doing this while on battery for sure, using CPU-Z I play around with the percentage of maximum processor state until I find a lower frequency that doesn't make machine feel annoyingly slow. I run the Ivy Bridge in the Dell I posted about above at 1.5GHz on battery and with lowered screen brightness I can get about 8 hours of web surfing (9 cell extended battery) out of my almost 10 year old machine.....
 

duronboy

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I've noticed that on games that should not stress my laptop in the least(I'm talking games with engines from 1999 like Quake) too aggressive of a reduction makes FPS sporadic.
 
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I'd also suggest searching https://forum.thinkpads.com/ and see if anyone has posted CPU upgrade info for your machine. From my experiences the 45W TDP real quad core mobile Ivy Bridge i7s went in machines with upgraded cooling systems like Dell Precisions/etc. Not sure I'd recommend a 45W TDP CPU in your system, how about the 2.9GHz (3.7GHz turbo) 2 core/4 thread i7-3520M instead? If you don't need all the threads, this may be a better option and stays within the TDP? The better single thread performance would benefit web surfing and light usage better then your slower speed quad core.......

That's a significant downgrade from the CPU I already have, if I can't upgrade I might as well stick with the 4C8T i7-3632QM CPU I already have. I can get a replacement 3632QM for $20 too if the CPU is dead.
 

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I suppose it is a downgrade. The real bummer is Thottlestop can't under volt Arrandale/Sandy Bridge/Ivy Bridge mobile CPUs, otherwise going to the 45W TDP i7 and under volting it and maybe lowering turbo speeds a bit would be the way to go.

Haswell and newer, and oddly enough Pentium M/Core 2 can be under volted by software, but not 1st-3rd gen Intel mobile CPUs.:facepalm:
 
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funkydmunky

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If I could buy a new laptop I would instead of trying to go the $60-100 route to fix this one, especially since most new laptops don't have easily removable drives and batteries anymore, or a second SATA port.
My point is because you aren't experienced in this and you have a shortage of $$, I would recomend getting a used Laptop that has the old-skool features you want, like a replacable drive etc... that way you know you're getting something that works. Work on the old guy when you have funds and want to learn and experiment. What if other things are fried beyond the MB? Then you are in a world of hurt.
 
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Thanks, that helps with the CPU install/removal. Although it doesn't seem to really describe what CPUs are compatible, just mention two generations and not if they are specific to certain models of the laptop.

My point is because you aren't experienced in this and you have a shortage of $$, I would recomend getting a used Laptop that has the old-skool features you want, like a replacable drive etc... that way you know you're getting something that works. Work on the old guy when you have funds and want to learn and experiment. What if other things are fried beyond the MB? Then you are in a world of hurt.

There isn't really anything else that could be fried other than the motherboard and possibly CPU, which is even cheaper to replace.

And I have been looking on eBay for months, I can't get anything even close to my laptop for any decent price. Even something considerably lacking like a Thinkpad T460 which I have been monitoring on eBay tends to go for around $120 or more.
 

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Limp Gawd
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Page 101 shows what CPUs were available on these machines.........

Also note they made several motherboards for these on page 100, some have the GT635 with 1GB or 2GB, and two don't. The ones without are labelled UMA. I suspect the ones without the GT635 may be a HM65 chipset which won't work with mobile Ivy Bridge.....
 
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Scratch that, what I originally posted here as a budget solution won't work as the LCD display cable is different.....
 
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