[Show off] Overclocking the octacore GS4

DSWR

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Hello, everyone.

I've spent the last few weeks working on a custom kernel purely dedicated to the GT-19500. This kernel is a custom design by myself to attempt to get the most power and performance out of the GS4. I'm not ready to release it as it seems to be rather unstable as you'll agree with shortly.

My main focus has been towards the twin processors though. As some of you maybe aware, the Exynos 5 octa-core chip is technically a 1.6GHz Cortex-A15 and a 1.2GHz Cortex-A7. This therefore means we technically haven't got the output power of Snapdragon 600 variant at 1.9Ghz. I've been running octa-core and quad-core variants of this phone side by side. Although technically the snapdragon 600 should technically be more powerful and also more economic, I've finally managed to beat the 1.9GHz of the Snapdragon on an octa core version. Originally, I managed to overclock the octacores A15 to 2.0Ghz. After much research I then looked into what many have mentioned on the forums. "Is there a way to get both processors going at the same time" entially, have a true octa-core processor running. I found a few flaws in the system trying to do this. First problem was the requirement to get them to work along happily. These cores would NEED to run at the same frequencies. I found out that you could infact get them on the same frequencies with a simple bit of underclocking. Forcing the A15 to run at 1.2Ghz and telling both chips to run at a minimum of 500MHz at exactly 1000000-μv. Now that they would work in harmony together, I had to then get them both working together. I had simulate a way to make the phone think it was in power saving mode, so the A7 would power, and then have the A15 working as well. Using a custom kernel, this actually worked, for a while, Sadly, the device did cook itself after...half an hour running. I think the problem was down to the voltage going through the cores at such power, especially seeing as both the chips were running where as it's typically just one. Before actually managing to cook the phone (It was completely knackered, overheated, will strip the phone down sometime showing pictures of the disaster) I did manage to clock it on geekbench at 2.8GHz. Hopefully I can do something about the phone, or even just buy another if required and release a couple of videos showing how this was all done. I believe it was the A7 that cooked as people have said to have managed 2.6GHz on just the A15 alone. Please note, If this was 2.8GHz between both cores, that's only 1.4GHz per chip as geekbench does recognise "8 cores" but samsung before only ran 4 of them!!!

TLDR: LUK WAT I DUN

2gslnc7.jpg
 

gollum18

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Will over clocking a octo core processor, even yield any noticeable performance improvements? I think not, octo core means 1 physical processor, 8 cores all clocked at the stock frequency. That means stock frequency * 8, why would you even need to over clock it?

Also it is designed to only run half the cores unless it is required to turn the other half on. Either with a need for performance or heavy use. Constantly running you device with all 8 on and over clocked will destroy both your processor and you battery.

Sprint GS3 Running TN's Msg and Chubbs
 

DSWR

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Will over clocking a octo core processor, even yield any noticeable performance improvements? I think not, octo core means 1 physical processor, 8 cores all clocked at the stock frequency. That means stock frequency * 8, why would you even need to over clock it?

Also it is designed to only run half the cores unless it is required to turn the other half on. Either with a need for performance or heavy use. Constantly running you device with all 8 on and over clocked will destroy both your processor and you battery.

Sprint GS3 Running TN's Msg and Chubbs

Well, I've noticed no touchwizz lagg, hahaha! Of course it won't show any benefits, the processor won't ever hit 2.8GHz. It's just an achievement and shows how hard you can push the device. I've since got another S4 octacore and have it running stable on only 4 cores as it was supposed to at 2.2GHz (A15) and still get the lovely battery life thanks to the A7. As mentioned in the above comment, it didn't ruin the battery but it did bake the phone. It actually burnt out a few circuits which I maybe able to repair with solder, will have to see. By the way, it wouldn't ruin the battery at all.
 

gollum18

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Well, I've noticed no touchwizz lagg, hahaha! Of course it won't show any benefits, the processor won't ever hit 2.8GHz. It's just an achievement and shows how hard you can push the device. I've since got another S4 octacore and have it running stable on only 4 cores as it was supposed to at 2.2GHz (A15) and still get the lovely battery life thanks to the A7. As mentioned in the above comment, it didn't ruin the battery but it did bake the phone. It actually burnt out a few circuits which I maybe able to repair with solder, will have to see. By the way, it wouldn't ruin the battery at all.

Sorry I didn't mean destroy as in make it unusable, I meant that it would drain it as in pretty rapidly. Pushing ant device that far beyond its means is very dangerous. For safe measure ocing should occur in steps of .05Ghz. And at the most it should be oced to a max of +.30Ghz. Of course every proc is different and some may be able to handle the strain more than others. But still I would never do that to my proc simply for benchmarking, as the previous poster said, that's insane.

Sprint GS3 Running TN's Msg and Chubbs
 

DSWR

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You pal are freaking crazy. Bet you had fun .

Sent from my GT-I9505 using Tapatalk 2

It's actually a lot of fun doing this stuff, haha. I stripped the S4 but there wasn't anything to see. Just burnt out a few connectors from the heat which were resoldered and the phone is working perfectly again. I think I'll use that phone primarily for testing and keep my new GS4 safe in my pocket, lol.

Sorry I didn't mean destroy as in make it unusable, I meant that it would drain it as in pretty rapidly. Pushing ant device that far beyond its means is very dangerous. For safe measure ocing should occur in steps of .05Ghz. And at the most it should be oced to a max of +.30Ghz. Of course every proc is different and some may be able to handle the strain more than others. But still I would never do that to my proc simply for benchmarking, as the previous poster said, that's insane.

Sprint GS3 Running TN's Msg and Chubbs

Ah, right. Thought you meant it would damage the battery itself. Yeah, 2.8GHz murdered the battery down pretty quick. And far pushing the device like this, just because it will hit 2.80GHz doesn't mean it's using that much. A processor is just like a car speedometer, it will show 0-100 but you may never take it up to 100. Basically, the processor is smart and will only use as much power as required. Overclocking is like de-limiting your car. It may not be allowed to go past 155mph but then you delimit it to go further. Yeah, it can cause damage, but on some phones its necessary to keep up with the times. People with GS2's, etc, may feel the requirement to overclock to use some of the newer games like real racing. I did do small tests on the way. On the A15 i went from 1.6GHz to , 1.8, 2.0, 2.2 and 2.4. I tested and they all worked fine. I got a nice little application that'll push the full power out of the processor properly so it was running on everything and the phone was only 5?C hotter than normal. I'd say that's a successful run. My new GS4 is clocked at 2.4GHz on just the A15 with the A7 at 1.4 for power saving and low performance. I also set the SD cards (built in and removable) to run at 3x the standard speed removing all traces of touchwizz lagg. I found the reason touchwizz has its lagg is because the standard SD card can't actually load the required files quick enough, that's why you may get a delay or two opening your camera. With my modifications all signs of lagg and delay are gone. Games won't even show loading screens. When I was clocking the GS4 at 2.8GHz on all 8 cores running same time It hit 77?C, so yeah, probably not a good idea to do. Now i've fixed the test phone I will be definitely be giving it another go. I think I can get all 8 cores working safely.
 

gollum18

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It's actually a lot of fun doing this stuff, haha. I stripped the S4 but there wasn't anything to see. Just burnt out a few connectors from the heat which were resoldered and the phone is working perfectly again. I think I'll use that phone primarily for testing and keep my new GS4 safe in my pocket, lol.



Ah, right. Thought you meant it would damage the battery itself. Yeah, 2.8GHz murdered the battery down pretty quick. And far pushing the device like this, just because it will hit 2.80GHz doesn't mean it's using that much. A processor is just like a car speedometer, it will show 0-100 but you may never take it up to 100. Basically, the processor is smart and will only use as much power as required. Overclocking is like de-limiting your car. It may not be allowed to go past 155mph but then you delimit it to go further. Yeah, it can cause damage, but on some phones its necessary to keep up with the times. People with GS2's, etc, may feel the requirement to overclock to use some of the newer games like real racing. I did do small tests on the way. On the A15 i went from 1.6GHz to , 1.8, 2.0, 2.2 and 2.4. I tested and they all worked fine. I got a nice little application that'll push the full power out of the processor properly so it was running on everything and the phone was only 5?C hotter than normal. I'd say that's a successful run. My new GS4 is clocked at 2.4GHz on just the A15 with the A7 at 1.4 for power saving and low performance. I also set the SD cards (built in and removable) to run at 3x the standard speed removing all traces of touchwizz lagg. I found the reason touchwizz has its lagg is because the standard SD card can't actually load the required files quick enough, that's why you may get a delay or two opening your camera. With my modifications all signs of lagg and delay are gone. Games won't even show loading screens. When I was clocking the GS4 at 2.8GHz on all 8 cores running same time It hit 77?C, so yeah, probably not a good idea to do. Now i've fixed the test phone I will be definitely be giving it another go. I think I can get all 8 cores working safely.

Good luck with that and let me know how it goes. I know for a fact samsung actually sets the max frequency below the safety threshold on purpose. I guess it's to account for the differences in processor performance.

Wow 77 Celsius? I hope you didn't injure yourself running it that high.

Sprint GS3 Running TN's Msg and Chubbs
 

DSWR

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Good luck with that and let me know how it goes. I know for a fact samsung actually sets the max frequency below the safety threshold on purpose. I guess it's to account for the differences in processor performance.

Wow 77 Celsius? I hope you didn't injure yourself running it that high.

Sprint GS3 Running TN's Msg and Chubbs

Burnt my poking finger but I'm manly and that so all is fine :eek: :eek: :eek: :eek: :eek: :eek:

Yeah, this processor has been held back on purpose. I can only imagine it's battery related performance being the reason to it.
 

Paul627g

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This sounds awesome. Nice to see there is still people out there willing to play and push the envelope.

Got my vote for pure awesomeness ;)

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Roberto Tomas

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Well, I've noticed no touchwizz lagg, hahaha! Of course it won't show any benefits, the processor won't ever hit 2.8GHz. It's just an achievement and shows how hard you can push the device. I've since got another S4 octacore and have it running stable on only 4 cores as it was supposed to at 2.2GHz (A15) and still get the lovely battery life thanks to the A7. As mentioned in the above comment, it didn't ruin the battery but it did bake the phone. It actually burnt out a few circuits which I maybe able to repair with solder, will have to see. By the way, it wouldn't ruin the battery at all.

Wondering if anyone who's overclocked it north of 2Ghz has kept it stable long enough for a benchmark. I imagine at 2.2Ghz it was pushing near 5k on geekbench yea? :)
 

BigDinCA

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Congratulations my man! Despite the fact that you did this on an 8-core S4, the story of this thread slid right in at the top of the BlinkFeed headlines on my HTC One. See how we're all getting along?

Once again, excellent work.