Dell Precision 7540 and 7740 Owner's Thread

Hello
got 2 kits of HX426S15IB2K2/32 (so 4x16) and it doesn't work, laptop won't boot. I tried all of them together as well as installing one by one in slot D, where the original module was, same result. Can't enter ePSA too, spins the fans then shuts down.
Did I have to change anything in the BIOS?
I got them as an open package deal, so somebody returned them before me. My only idea is that all of them are bad, but I can't even memtest them.

 

That is the same ram kit I am using in my 7740, in the slots under the keyboard. Which BIOS are you using? I suppose all four sticks could be bad given that they were already returned. If it was a good deal you could try to get Kingston to swap them out under warranty.

 

BIOS 1.4.0, latest they have. I'm surprised I'm not getting any diagnostics out, like power led blinking me an error code.
Anyway, will try to return.
What's the tested Samsung 32G module? M471A4G43MB1 ?

 

Strange, I have the same 2 kit my 7740 and works flawlessy. Just one thing: the first time you put on the new modules it can take a lot of time (1/2 minutes) to boot up, so be sure to wait enough time before force the shut down.

 

!!! :facepalm:
It took about 30s to show Dell logo.
Thank you!

 

So I received my machine this week...

From Dell: M7740, 9980HK, RTX4000, 8GB, 256GB class40, FHD
From Amazon: 4x32GB Samsung, 3x Adata SX8200Pro 1TB

Problems with the upgrade...

• I thought there was an issue with the RAM, but just needed some patience... it takes a while to initiate!
• After several hours, I found a combination of slots to have 3 of my 4 SSDs to register with Win10 (DiskManager & Device Manager) - the 256GB + 2 of the Adata drives... any advice appreciated!

(These Adata drives are good value for money, but in lieu of the detection for Win10 driver, I would urge you to spend the extra bucks on the EVO Plus/Pro)

I need single core boost for my work, and found that best results are using TS set to x51 for 1, 2 and 3, core boost. The task scheduler shuffles the "single core" workload and you have perpetual boost at around 30W power draw.

 

So how much CPU wattage can the 7740 cooling dissipate reliably before thermal throttling? The review on 51nb suggests about 75 watts? Is that about what others are seeing?

 

I've been using my 7740 for a few days, and it is still has "stock standard" cooling.

With -110mV on CPU/Cache and -25mV GPU, it maintains 3.6-3.8 gHz while running CB R15 multi core benchmark, after the 28s boost limit was hit.
(I am in the Ukraine at the moment; ambient tempreture sub 20`C.)

Hope this helps...

 

With original cooling (no repaste nor other mod) I think that thermal cap for sustained work loads is more in the 60W area than in the 75W.
With a good repaste maybe you're already in the 75W. With repaste and screw mod (you can find my test in the previous pages) you can go to the 90W area, but there's still the power limit that after some times bring back the cpu to 75W.

Anyway is always recommended to use undervolt of at least 100mV to have a good perfomance boost.

 

I just ordered a 7740 with the minimum RAM thinking I would just install a couple of DDR4-3200 modules. Now I read here that people are having trouble. Can anyone tell me what specific 8Gb x2 or 16Gb x2 module kits will work?