3920xm vs. 3940xm

[Gunner6669]

Looking for an upgrade for m18x r2 which currently has a 3840qm @ 4.0ghz all core. I asked this question in another forum awhile back and was told the 3920xm seemed to have more oc headroom, is that true? The price of these chips are half the cost compared to the last time I thought about upgrading so I’ll probably go through with it this time lol. I already have a 3 heat pipe cooler, 32gb 1866mhz ram, gtx 1080, Samsung 512gb nvme, and ax210 so this would be the remaining upgrade for my system I’ve had since release. 

[Gunner6669]

I guess the real question I should be asking is what are your guys everyday gaming overclocks on these chips? I don’t really care about max oc since I don’t do much benchmarking but I am hoping for a decent boost over 4ghz to help out the 1080 in the cpu limited games. 

[Maxware79]

I used to run my 3920XM at 4.2. That wasn't with any change to the voltage so they can go much higher if you want to play with them more than I did. 

[Jerryzago]

43 minutes ago, Maxware79 said:

I used to run my 3920XM at 4.2. That wasn't with any change to the voltage so they can go much higher if you want to play with them more than I did. 

How do you mess with the voltage on a m18x r2? Mine barely hits thermal throttling with 3,9GHz.

[Gunner6669]

12 minutes ago, Jerryzago said:

How do you mess with the voltage on a m18x r2? Mine barely hits thermal throttling with 3,9GHz.

That doesn’t sound promising when my 3840qm sits at 4.1 on 1-2 cores and 4.0 all core and sits at 82 degrees while gaming. 

[Maxware79]

2 hours ago, Jerryzago said:

How do you mess with the voltage on a m18x r2? Mine barely hits thermal throttling with 3,9GHz.

 

You should be able to use Intel XTU to do all the overclocking you need on XM chips. You may need an older version of XTU for these 3rd gen processors, I remember having some issues a few years back when trying to use a more recent version. It's been along time since I've messed with it though. 

[Jerryzago]

14 hours ago, Gunner6669 said:

That doesn’t sound promising when my 3840qm sits at 4.1 on 1-2 cores and 4.0 all core and sits at 82 degrees while gaming. 

I know. I can set 4.2 and game on it, but it reaches 95 degrees easily and throttles to 3,7. It barely keeps 3,9 which is stock boost speed for this CPU!!!

 

12 hours ago, Maxware79 said:

 

You should be able to use Intel XTU to do all the overclocking you need on XM chips. You may need an older version of XTU for these 3rd gen processors, I remember having some issues a few years back when trying to use a more recent version. It's been along time since I've messed with it though. 

I do use an older XTU, but it doesn't have undervoltage control. I can up the voltage but no drop. I also have the unlocked bios, but still there is no option to drop voltage a bit to give it some headroom. My 3720qm did reached 3.8 GHz and the three pipe heatsink helped it stay below 90 degrees all the time.

[aldarxt]

I have found setting 44,43,42,41 for both work best for both, I've also set higher at 44,43,42,42 but thats when they start heating up but the 3920 can handle the heat better, I can leave 3920 there but feel just under max is better, not to push it all the time. I've also set 44,44,43,42 but that starts throttling.

[Gunner6669]

1 hour ago, aldarxt said:

I have found setting 44,43,42,41 for both work best for both, I've also set higher at 44,43,42,42 but thats when they start heating up but the 3920 can handle the heat better, I can leave 3920 there but feel just under max is better, not to push it all the time. I've also set 44,44,43,42 but that starts throttling.

Hmm. 4.1-4.2 all core seems to be what people have settled on, I was hoping to see like 4.4. So now is that 100-200mhz worth the effort, cost and extra temperature. Benchmarking it would make a difference but I doubt it’s a noticeable difference in actual gaming especially with modern games pushing all the cores. My 3840qm is set at 42,41,40,40 and it runs in the low to mid 70 degrees in most games and I the max I’ve seen was 81. 

[aldarxt]

3 minutes ago, Gunner6669 said:

Hmm. 4.1-4.2 all core seems to be what people have settled on, I was hoping to see like 4.4. So now is that 100-200mhz worth the effort, cost and extra temperature. Benchmarking it would make a difference but I doubt it’s a noticeable difference in actual gaming especially with modern games pushing all the cores. My 3840qm is set at 42,41,40,40 and it runs in the low to mid 70 degrees in most games and I the max I’ve seen was 81. 

The 3840qm is a good cpu, its just not overclockable so if you just want to game then stick with it. But if you like experimenting with overclocking then the 3920xm is better than the 3940xm just because of the temps

[Gunner6669]

I do enjoy tinkering with older hardware despite most of the time it leading to frustration lol. I think for the price of $83 CAD for the 3920 I might just pick one up and if I get bored I’ll throw it in and mess around. I currently have an offer on one for $70cad or roughly $50usd so we’ll see what happens. 

[aldarxt]

24 minutes ago, Gunner6669 said:

Hmm. 4.1-4.2 all core seems to be what people have settled on, I was hoping to see like 4.4. So now is that 100-200mhz worth the effort, cost and extra temperature. Benchmarking it would make a difference but I doubt it’s a noticeable difference in actual gaming especially with modern games pushing all the cores. My 3840qm is set at 42,41,40,40 and it runs in the low to mid 70 degrees in most games and I the max I’ve seen was 81. 

I have had my 3940xm and 3920xm hit over 100c but that was OCing 45,44,43,42 so i keep it under. But as @Maxware79 said XTU can regulate voltage I might try it

[Gunner6669]

20 minutes ago, aldarxt said:

I have had my 3940xm and 3920xm hit over 100c but that was OCing 45,44,43,42 so i keep it under. But as @Maxware79 said XTU can regulate voltage I might try it

Thanks for the info. I’ve already found an older version of xtu that works with 3rd gen cpus so I’m already on my way to trying it lol. 

[ssj92]

You can OC in BIOS in M18xR2. No need to mess with XTU. 

 

You can also use Throttlestop. 

 

Just increase turbo power limits, pri plane 800 and increase multiplier. 

 

I use 4.1Ghz 24/7 clocks without any voltage on 3920XM. I can go as high as 4.7Ghz but that requires lots of voltage and a fan under the laptop.