P651RE6 cpu & memory upgrade

What is a surefire way for one to know whether a P651RE6 (with 6700HQ, GTX970M and 15.6" 4K) is upgradeable to 6820HK and 64GB DDR4? Thanks in advance!

 

The memory can I believe, should be DDR4 so throw in some big sticks.

The cpu 100% can't. It's soldered to the motherboard.

Source: I own a P650.

 

Thank you, Galm!

 

You can make sure the 6700HQ is working at full speed all the time with an undervolt if you are in the tweaking mood.

 

@Zazula Yep, 16GB x 4. And while you can't replace the CPU, aforementioned undervolt will help with temps at least.

 

Thank you all, once more!
Although I feel a bit Slowpoke-ish that I was still thinking in terms of socketed CPUs.

@Meaker@Sager, what is iyo the best undervoltage guide for me to follow? Moreover, should I also undervoltage the memory?

@Prostar Computer, should I stick to 2133 MHz sticks (no pun intended)? Do I gain anything substantial by going to higher MHz RAM so that I get a lower CAS in 2133? Also, I noticed in my local market one 4 X 16 set is more expensive than two 2 X 16 sets; therefore my question is: is it necessary for all four sticks to be a single matched set?

 

Punny! "Substantial", no, but the lower CAS may prove somewhat noticeable. I prefer to stick with the speed that matches the IMC for stability's sake, although going with something a tier or two faster isn't necessarily a definitive way to bluescreen yourself to insanity.

As for matching, it's definitely recommended - again, for stability's sake - but people get away with mixing brands, at least. I'd avoid mixing speeds & CAS timings in addition to that, though.

 

The best of both worlds as far as RAM is concerned is the Kingston HyperX DDR4-2400 CL14.

 

Hmm, eventually I don't see any difference in timings, because Kingston spec sheets give:
HX421S13IBK2/32 32GB DDR4-2133 CL13, JEDEC/PnP: DDR4-2133 CL13-13-13 @1.2V
HX421S14IBK4/64 64GB DDR4-2133 CL14, JEDEC/PnP: DDR4-2133 CL14-14-14 @1.2V
HX424S14IBK2/32 32GB DDR4-2400 CL14, JEDEC/PnP: DDR4-2133 CL13-13-13 @1.2V
HX424S15IBK4/64 64GB DDR4-2400 CL15, JEDEC/PnP: DDR4-2133 CL14-14-14 @1.2V
HX426S15IB2K2/32 32GB DDR4-2666 CL15, JEDEC/PnP: DDR4-2133 CL12-14-14 @1.2V
64GB DDR4-2666 kit: n/a

 

Note the timings you have bolded are the timings used for the JEDEC 2133mhz booting profile.

 

I did so, because I think the laptop won't be able to clock at 2400 — or at least I don't know how to make it do so.

 

The 16GB RAM chips work okay, I tested a pair.
Now in need of the undervoltage guide.

 

Undervolting is pretty easy. You can use Throttlestop or XTU. Given XTU tends to play funny and eat more CPU than it should, I recommend TS.

Grab ThrottleStop from the thread here: http://forum.notebookreview.com/threads/the-throttlestop-guide.531329/

For a quick and dirty run down:

1. The worst thing that will happen with undervolting is that you crash/BSOD. Not so bad really, but I don't recommend having anything important open as you could corrupt files/OS as any BSOD/crash could do.
2. Run TS
3. Click the "FIVR" button
4. Click the "OK - Save voltages immediately" radio button in the bottom right.
5. Click the "CPU Core" radio button under "FIVR Control"
6. Tick the "Unlock Adjustable Voltage" box.
7. Under "Offset Voltage", we'll start with -100mv
8. Repeat steps 5->7 but with "CPU Cache"
9. Click "OK" to return to the main screen.
10. Click "Save" in the bottom right and "Turn On" to enable the changes.
11. Keep an eye on it, run some benchmarks (Cinebench/Aida64/whatever).
12. If it's stable, re-do steps 3->8 and increase the undervolt (I usually go in 20mv increments). If you crash, not

For reference with the 6700hq and TS in general:

• Almost all 6700HQ chips will run at -50mv without issues.
• Most will run -100mv without issues.
• Some will run -150mv or more.
• You can use 4 radio buttons on the top left as "profiles" to save various settings.
• For absolute performance, you can un-tick the "BD PROCHOT" box which coupled with the undervolt should allow you to run 3.1ghz across all 4 cores without power or temp throttling.
• Keep in mind, that just because an undervolt is stable when you benchmark and idle, it may not be stable across the entire range of clocks. If you randomly crash/BSOD some time later it's probably the undervolt.

 

Thank you, @Stooj, your help is appreciated!