Dell Precision 7540 and 7740 Owner's Thread

Wow that is close to what the 9900K could do in the MSI WT75.

Are there any hi-res photos of the 7740 9980HK motherboard? I am curious what the VRM is like and if it is designed to sustain this level of performance. It could be that those lower TDP values are set based on the assumption that you have a 115W Quadro card.

 

About to buy a 7740, wondering if the 9980HK or 2286M are worth it, if under heavy load these will throttle back correct in which case an i7 might be a better option?

 

1.0 with liquid metal repaste. Last night I've just tried to push to power limits to 150w PL1 140w PL2 and suddenly I am again throttling at 100w and then 75w shortly afterwards. XTU and Throttlestop both seem to be unable to shift that limit and the trick I've tried before (of lowering PL1 and PL2 and then raising again) doesnt seem to do it this time. I am puzzled, there seems to be no consistency in how this machine handles power limits, like there is another type of limit that kicks in, just not always.
Another oddity is that sometimes when I use my 240W power brick my PL1 drops to 35w (again cannot override it with XTU or Throttlestop), but then a few hours later without me trying to fix it its back to 100w. Will keep trying to get around it, but at the moment I am stumped and running short of ideas of what to try next. If I hadnt spent 2 days of setting up everything I would try a windows re-install as I do see some DPTF error messages in event viewer, which may or may not be relevant to the power limit issue:

ESIF(8.5.10103.7263) TYPE: ERROR MODULE: DPTF TIME 290824 ms
DPTF Build Version: 8.5.10103.7263
DPTF Build Date: Dec 12 2018 18:51:29
Source File: ..\..\..\..\Sources\Policies\ConfigTdpPolicy\ConfigTdpPolicy.cpp @ line 311
Executing Function: ConfigTdpPolicy:nOperatingSystemConfigTdpLevelChanged
Message: ConfigTdp not supported.
Participant: TCPU [4]
Domain: PKG [0]
Policy: ConfigTDP Policy [1]

Edit: and just like that Throttlestop power limit settings work again. Only thing that happened since previous post was me installing Dell Power Manager (which did not fix the 100w limit) and then laptop waking up from sleep. Will look out for next time this happens so that I can see if I can reproduce the steps taken to allow going above 100w limit. Event viewer still showing above event currently, so its probably not related to the limit either.

Edit 2:
Managed to push power limits to 145W/140W and hit new CB20 high of 4635 points. Though temps did hit 100c at the end of benchmark, so I dont think its a realistic 24/7 setting.

 

Anyone knows of good compatible 2x32gb (or 2x16) for the 7740?

 

The Kingston HyperX 32GB 2666mhz kit HX426S15IB2K2/32 works well for me. For 64gb, a crucial kit should work fine once it is available, as well as the Samsung 32gb modules.

 

Thank you, appreciate it. Not expensive either

 

I also recommend the Dell drivers. I've tried NVidia DCH: In my case, Dell versions "somehow" know how to deal with docking & undocking to multiple dockingstations with different monitor configuration. With the NVidia ones you get sometimes blank screens or driver stops working and all my running firefox windows are dark.
The dell drivers are "almost" reliable - sometimes resume from standby fails. For this situation this fix works for me relaible since 20docking cycles (Every day 2-3cycles): Before docking, do a complete power disconnect of Dock and monitors, connect power supply, then I connect dual USBC connects, then press power button for resume. I hope this will work reliable, I have no more ideas.
Btw: I am using the external monitors in discrete mode. With orignal NVidia and Dell ones I get sometimes t TDR_TIMEOUT bluescreens, this I fixed by increasing the timeout.

 

Just bought a brand new 7740 (with i9-9980HK), and bought it with the cheapest RAM/storage so I can upgrade.

What is the absolute fastest single 32GB stick of RAM the 7740 can handle, and that I can by online somewhere? The Dell configurator mentions DDR4 3200MHz, but not for a single stick of 32GB. The idea is to first buy 1 stick, and over time, money permitting, eventually put 128GB in it, all 4 at the highest speed possible.

Michael

 

Dell is only selling 32GB modules at DDR4-2666 as far as I can tell. Originally, only Samsung modules were available in this capacity so that is what Dell was using. There are a few more options now so Dell may be using multiple vendors.
https://www.newegg.com/p/0RM-002H-000X1

Options for 32GB at DDR4-3200 are very limited. The only one that I am seeing is this Crucial module which is probably hard to find (out of stock at both Newegg and Amazon).
https://www.newegg.com/p/N82E16820164170
https://smile.amazon.com/dp/B083VV2M8M

 

Thanks a lot for your detailed answer!

I'm now wondering, is it even really worth it to try to track 4 of these down and cram them into my new 7740? What kind of performance benefit would I see? Also, I have read in this thread that some people say using certain kinds of RAM can lead to instability. I obviously don't want that, even if I lose a tiny bit of speed.