4th gen i7 memory

[mad_jock]

Just a warning.

After taking a look at a laptop for a colleague which was acting up.

These 4th gen machines need 1.35v ddraml

His appears to have been delivered with 1.5v and as far as I can tell this has cooked the proc or some other important bit of gubbins.

So if you getting a new computer just check what ddram they have fired in it. Amazon have agreed to take his back so we have cloned his disk and packaged it up.

It was all very weird how it failed though. I wonder why they haven`t stuck an extra lug or something on the 1.35v slots to stop you putting the 1.5v in.

[Bushfiva]

DDR3 and DDR3L are electrically compatible. DDR3L works fine in DDR3 devices and, indeed, tends to come off the same production line as DDR3 but simply passes the functional test at 1.35V.


As for the other way around, DDR3 SODIMMs on a Haswell-based motherboard should simply fail POST with a double beep. Both the memory and notebook will be OK: putting the right memory in will resolve the issue.

[atakacs]

I really don't see improper ram "frying" the processor. Should (as mentioned) trigger a POST error message or beep.

[mad_jock]

Well it does.

And it doesn't refuse to work either or give any warning beeps which is why I posted the warning.

I only spotted it by accident when looking at a forum and they had some screen shots of CPU-Z up and it had memory voltage 1.35 and when I looked it was 1.5v on the laptop for one bank.

Then doing a search turned up on a gaming forum the fact that running 1.5v DDram causes some over heating in the gubbins, damaged to the CPU IMC due to a different potential difference and increased power drain from the battery. And over time breaks things giving exactly the same problems as we were experiencing. It works fine for months then starts crashing. If you use intensive memory applications it speeds up the process.

Mind you if you have an Acer you will just think its the normal aging process which is occurring.

[Booglebox]

I've fried memory slots before by putting in the wrong RAM :} but not processors...

[llondel]

The machine is defective if it allows you to put 1.5V on the RAM when that would blow up something else on the board. The RAM itself is blameless, it will just report what it is and what it wants, then the BIOS should look that up and configure the hardware to supply it. Clearly there should be checks in the BIOS to prevent something bad happening.

[Helix Von Smelix]

My colleague normally fry their laptops by using them on a soft surface.

Blocks the cooling don't you know. :ugh:

[mad_jock]

Nope wasn't that.

And it also wasn't an upgrade job fitting different voltage it two different banks.

Most of the stuff I can find is for overvolting of I7 above 1.65v causing damage from 1.5v



Upgraders: 1.35V memory is required! (http://rog.asus.com/forum/showthread.php?33744-Upgraders-1.35V-memory-is-required)

This was the thread I got the biggest hint from.

Anyway you can choose to believe what you want. But check your manuals and check what memory you have if you have a laptop. If its meant to be 1.35 and you have it running at 1.5v it can do damage.

[Helix Von Smelix]

it may be that the memory is capable of 1.5v. Not so easy to play with the BIOS settings on a laptop. Download a prog, may be from CPUID, which will tell you what voltage it is running at.

[mad_jock]

CPU-Z is the said program that does that for you.

Not being an overclocking type this has been a bit of an eye opener for me to be honest. It seems to be mainly an overclocking and mobile Haswell issue.

I can only presume that companys get these laptops in sans memory and hard disk and make them up to order then punt them out.

Just given up on acers forever and got one of the ROG machines mainly because it has two fans and the hot air goes out the back.

Almost 2 years to the day and exactly the same time period to the day as my last one the CPU temp sits at 85deg C and the thing shuts down if you do anything remotely intensive Acer really are a heap of crap. Lets see if paying 250 quid more for the gaming ASUS does the trick. Oh and it turned up with 1.35v

[Booglebox]

mad_jock: open it up and clear the dust out? :}

[mad_jock]

I had done all the usual stuff with laptops. But when it crashed it wasn`t a thermal shut down. It was screwed up colour blocks followed 10 mins later by a memory dump.

It was only 6 months old.