Laptop has charging stutters

[jjphillips002]

I'm not really sure how to describe this. While playing a game, or running FurMark, my laptop will quit charging for a minute, I get a huge FPS lag spike, and then it begins charging again. It will keep doing this most of the time.

I have learned that giving it better ventilation helps sometimes, but not always. Today, I decided to run it through some tests. But before that, I cracked open the back, took the heat sinks off the GPU and CPU and took that tacky, nasty, silly puddy shit that was on it off and put some AS5 I had on it.

First off, I ran Prime95 for 30 minutes. CPU temps didn't go over 72C. I ran FurMark at 1600x900, 4xMSAA, Dynamic background and Burn in selected, and watched the GPU temp. Hit 80C after about 20-30 minutes, but apparently that's normal in laptops. Averaged around 75-76C. Next, I really laid it to. Did the same FurMark test while also doing Prime95 for about 20-30 minutes. This got the CPU to heat up and GPU to heat up to really test the cooling. One or two cores finally peaked at 100C, but dropped back down to 95-96C. GPU didn't go much over 90C so not a big change there. I let this go on for a while, no charge power mode changes or anything. After about 20 minutes though, it started having charging stutters, causing the FPS to lag, of course. I checked on HWMonitor for power readings, temps, yada yada. Nothing was over 100C. CPU was about 95C and GPU at 90C. Tjmax being 105C for both chips, so I'd say I'm in the clear anyway, but I was thinking a certain threshold would cause it.

At this point, I turn off Prime95 - no more stutters. Turn it back on, temps go back to 95C, still no stutters.

Without Prime95 on at all, I run a 1920x1080 FurMark preset benchmark at about 12FPS. Charge stutters everywhere. GPU wasn't even past 80C.

Here's the fun part. My battery is not hot at all. So I'm not too sure my laptop is cutting charging for just a half second to keep it cool. I also don't think it's bad considering I can go for 4-5 hours use on a charge. Lastly, it doesn't make sense either if my charger wasn't able to deliver enough power to have a net gain in power either, since running FurMark and Prime95 should make the CPU pull more power. It is POSSIBLE I have a short in my cable, but I'd pay someone $100 to find it because I've tested it all over to see. SO WHAT IS GOING ON HERE PLEASE HALP

Samsung 7 Series Chronos 17.3" laptop
i7 3635QM
nVidia GT650M 2GB GDDR5
8GB DDR3 RAM
Windows 8.1

PS: it takes longer sessions at 1600x900 windowed for this to start compared to 1920x1080 fullscreen. This is also consistent in FurMark. I can run 1920x1080 and charging stutters happen almost immediately. Run the same benchmark in 1600x900 right after and nothing happens. Also, when gaming, my temps don't go over 72C most of the time.

Thanks for your help

 

[C12Friedman]

I'm thinking you'll need to get back inside and look the motherboard over real good for swollen or leaky capacitors - even surface mount ones. I'm thinking offhand that one cap at least may be shot.
How about the power adapter itself, it's not getting too hot? Possibly a loose power jack or bad power adapter cable (especially if you have "power saver mode when on battery" selected) Do your temps start slowly dropping during these slowdown/stuttering periods

 

[jjphillips002]

The charge block does get pretty warm. Temps do drop normally 2C as soon as it happens and then normalizes.

And I have it on High Performance on both power settings. I thought maybe that having the same plan would allow a smooth transition between on battery and plugged in, but I was wrong, haha. I'll look for a damaged capacitor.

 

[jjphillips002]

I'm thinking you'll need to get back inside and look the motherboard over real good for swollen or leaky capacitors - even surface mount ones. I'm thinking offhand that one cap at least may be shot.
How about the power adapter itself, it's not getting too hot? Possibly a loose power jack or bad power adapter cable (especially if you have "power saver mode when on battery" selected) Do your temps start slowly dropping during these slowdown/stuttering periods

The charge block does get pretty warm. Temps do drop normally 2C as soon as it happens and then normalizes.

And I have it on High Performance on both power settings. I thought maybe that having the same plan would allow a smooth transition between on battery and plugged in, but I was wrong, haha. I'll look for a damaged capacitor.

Just got the laptop back together. No blown or swollen caps that I could see. I went over it well. I even checked the charge port. Looks perfect. Made sure the fans were working. I'll test the block by putting it somewhere cool

EDIT: I think you may be onto it about the charge block. Doesn't seem to stutter right now. Temps have been pushed to max again with stress testing and still no stutters. Just took the block out of the fridge to see what happens.