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

[Cyber Akuma]

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-metal-lenovo-ideapad-g780-gaming-entertainment/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_of_Intel_Core_i7_processors#Ivy_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?

[RONOTHAN##]

7 minutes ago, Cyber Akuma said:

that's when I noticed that I could get a replacement motherboard for this exact model for about $60-70. 

That's still too much to make sense, you can get a whole laptop from that era for that price. You really are better off just selling the laptop for parts on eBay, making whatever you can get for it, then starting new. 

 

It is likely only the motherboard that went bad, though there's no way to tell if the CPU ended up dying at the same time without putting it in a motherboard and hoping for the best. I would be surprised if it broke the CPU at the same time, but anything is possible. 

[Cyber Akuma]

4 minutes ago, RONOTHAN## said:

That's still too much to make sense, you can get a whole laptop from that era for that price. You really are better off just selling the laptop for parts on eBay, making whatever you can get for it, then starting new. 

 

Believe me, I have been looking, cheapest for something that doesn't even come close to mine CPU-wise (To say nothing of it's discrete GPU) is $120-ish.... and 90% of those are missing the battery AND AC Adapter. And that's not even bringing up the fact how easily upgradable/replicable parts of mine is or that it's a 17 inch model.

[Crunchy Dragon]

19 minutes ago, Cyber Akuma said:

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?

Judging from my somewhat basic knowledge of how computers work, my first guess would be the motherboard. If you can pull the entire board out, I'd recommend looking for any scorch or burn marks. If there's a burning smell, there should be some visual evidence to accompany that.

 

Your CPU might be okay. At this point however, why not just buy an entirely new laptop?

[Cyber Akuma]

6 minutes ago, Crunchy Dragon said:

Your CPU might be okay. At this point however, why not just buy an entirely new laptop?

I can't afford a new one, and I can't find a used one that comes close for anywhere less than a new motherboard and CPU would cost.

 

It's a 4C 8T 3rd gen i7 with a discrete GPU, 17 inch screen, easily-accessible RAM and HDD, and optical drive that can be replaced with a second SATA drive. I am not going to find something like that even used for less than a replacement motherboard and CPU. Closest I can find is a Thinkpad T460, which is a 6th gen i5 that is still out-performed by my laptop's 3rd gen i7, has no discrete GPU, no optical drive/second SATA slot, and is 14 inches.... and those still tend to go for around $120 on eBay and tend to be missing the AC adapter.

[BondiBlue]

7 minutes ago, Cyber Akuma said:

mine CPU-wise (To say nothing of it's discrete GPU)

It's really not that hard to find something that would be as good as your old laptop these days. The CPU (which has 4 cores and 8 threads) has a PassMark score that isn't much higher than the AMD Athlon 240GE, a low end dual core CPU from 2018. Granted, that's a desktop chip, but as long as you aren't looking for something newer with a U-series chip (low power, found in less powerful laptops) you'll be fine. 

 

As for the GPU - it's really not a powerful chip. The PassMark GPU test puts it in line with the Intel HD Graphics 5000 - integrated graphics found in U-series Intel CPUs from late 2013. It's nice that it has dedicated video memory, but that's about the only advantage it has. Integrated graphics on something a bit newer (probably Skylake or Kaby Lake era) would likely be a more than suitable replacement unless you really need something with dedicated VRAM. 

[Cyber Akuma]

If I wanted the second SATA slot and a 17 inch screen it is, there is no way I am going to find a 17 inch one for the price of the motherboard. Everyone keeps saying you can, but I have been scouring eBay for the last two months and nada.

 

I do not want to get a new laptop, I want to fix my current one. I am not interested in buying an entirely new laptop.

[An0maly_76]

Better off to find a similar replacement machine if you really like it that much. But I think everyone gets into this momentary "fix it, don't want a new one" mentality initially. But you can probably get one of those with an upgraded processor cheaper than it would be to fix what you have. Not to mention the highest-tier processor dates to 2012.

 

What's more, once you get used to something newer and faster, you'll wonder how you ever did without it. Believe me, the interim 3600X build I did while my Asus B550 board was being RMA'd taught me I'll not likely trade down from 8-12 cores. Even that 3600X feels slow to me now.

[Cyber Akuma]

I get everyone is trying to help, but honestly? I am starting to get a bit agitated that everyone is just saying I should buy a new laptop when I already tried that route and can't afford it.

 

I have looked, if you can find a 17 inch laptop with an optical drive (YES I do use it, AND i constantly swap it with a secondary drive as well) that gives me easy access to both drives without having to open up the entire laptop and has at least the CPU and GPU capabilities of my current one for less than the price of a new motherboard, or even a new motherboard and CPU, which would still be around $60-120, then please post the link to it. Because otherwise from my months of searching, such a thing does not exist at that pricepoint.

 

Please stop suggesting I buy a new laptop.

[Crunchy Dragon]

At this point, replacing the motherboard and praying something else down the line(RAM, CPU) didn't get fried is going to be your best option, if you're that set on keeping your current laptop.

 

Just make sure to budget for replacing things if they also bit the dust, and maybe back up all your important data from it just to be safe.

[Cyber Akuma]

The data on my HDD is already safe, and I have backup RAM modules to use. The RAM itself is also fine because ironically one of them went bad shortly before all of this happened and I have sent it in for RMA since.