Re: RAN 1.35v vs 1.5v

In alt.comp.os.windows-10, on Thu, 28 Jan 2021 01:33:08 -0500, Paul
<[email protected]> wrote:

>micky wrote:
>> In alt.comp.hardware, on Tue, 26 Jan 2021 19:22:59 -0500, Paul
>> <[email protected]> wrote:
>> 
>>> micky wrote:
>>>> I wanted to get more RAM for my newly-acquired PC
>>>> Entering the make and model, HP EliteDesk 800 G1 Small Form Factor
>>>> Crucial suggests only CT2K102464BD160B
>>>> DDR3 PC3-12800 • CL=11 • Unbuffered • NON-ECC • DDR3-1600 • 1.35V •
>>>> 1024Meg x 64 •       $76 even cheaper at NewEgg,  
>>>> Kingston suggests only KCP316ND8/8
>>>> Specs: DDR3, 1600MHz, Non-ECC, CL11, X8, 1.5V, Unbuffered, DIMM,
>>>> 240-pin, 2R, 4Gbit   $98
>>>> The items are in different order but the main difference seems to me to
>>>> be  1.35v vs 1.5v.   
>>>> That seems important, right?  How can they be different for the same
>>>> computer?   (I'm not really concerned about price unless they could sell
>>>> it cheaper by making it at the wrong, lower voltage. )
>>>> Do I need to look up what the computer puts out?   Would one of these be
>>>> overclocked if the computer puts out 1.5v and the other underclocked if
>>>> the computer puts out 1.35? 
>>>> I already have 2 sticks,  Do I want to get the same voltage that they
>>>> use, whatever that is? 
>>>>    ------
>>>> Other differences are 
>>>>   Crucial says PC3-12800 but Kingston doesn't include that.  
>>>>   Kingston says X8, 2R, 4Gbit but Crucial doesn't include any of that. 
>>>> Does any of that matter? 
>>>>    ------
>>>> FTR, I only looked at Newegg because Crucial was out of stock. NewEgg
>>>> says "Ships from China. Newegg Most customers receive within 10-32
>>>> days."
>>>> Hmm.  At
>>>> https://www.newegg.com/crucial-16gb-240-pin-ddr3-sdram/p/N82E16820156047
>>>> it says sold and shipped by Ram-Store and when you click on 12 New from
>>>> $88.46 , it goes to the bottom of the page where they have 12 vendors
>>>> selling the same thing.  Just like Amazon does it. I only looked at the
>>>> first 5 but one is in Hong Kong and "Most customers receive within 4-17
>>>> days.".  One is in the US and "Most customers receive within 7-9 days",
>>>> all except Hong Kong for the same price!! (For Hong Kong and the next 7
>>>> the price gets higher.)
>>>> But this doesn't matter until I understand the voltage question. 
>>> 1.35V DIMMs run in a 1.5V motherboard.
>>>
>>> There should be a FAQ with the details around somewhere.
>>>
>>>    https://superuser.com/questions/564175/1-35-v-ram-in-a-1-5-v-system-will-it-fry-or-overclock
>> 
>> First answer is:  As far as I know, the voltage of the board in the bios
>> shows the max voltage that can be drawn by the hardware, so if the RAM
>> only draws 1.35, that's all it should use. I'm not 100% though so this
>> is purely a comment, not an answer.
>
>If your machine uses SODIMMs, I must have selected the wrong
>item from the Crucial list.

No, it doesn't us SODIMMs. The two smaller versions of the same name do,
but the my SFF and the tower version use dimms. 

>If you have part numbers on the existing modules and you're
>happy with them, then that's likely just as good of a
>choice as anything else. If you got "fancy" products with
>low CAS, they wouldn't help, because the slowest memory
>in the machine determine the speed choice made by the BIOS.

Okay, so there's no point in looking for lower CAS.  Someone suggested
buying 4 8's but I don't want to spend extra money.  (The first machine
I bought, the one that didnt' work and was the wrong model too, had all
4 slots filled with 4's, and I thought that might be the standard in
refurbishing, but this one has 2 8's .) 

>But if supplies were limited (like the Crucial being out of
>stock), I was looking around to see what could be fitted
>from the existing pool of product.
>
>I'm really surprised you can find branded Samsung DIMMs/SODIMMs.
>Samsung sells product more to businesses than to end users.

If I'd known that, I might not have looked!    Several places that
google found were out of stock, but as is not uncommon, Amazon had it,
although its sold and shipped by Dataram, a company that's 54 years old
and made ram themselves, and I think they still do.   And it's even in
New Jersey so maybe I'll get it a day or two earlier since I'm in
Baltimore. (though it says 14 days.  That's okay.)

So I got the Samsung from them via Amazon. 
https://en.wikipedia.org/wiki/Dataram although the info on this page
stops at about 2011. 
http://memory.dataram.com/  Their webpage is in English, French, German,
and Japanese!

>The SPD table shows what the DIMM expects in terms of voltage.
>The SPD chip receives power right away, and the BIOS reads the SPD.
>The BIOS "turns on" the VDIMM regulator, only when it has
>determined what the strategy is. So RAM is "commissioned"

This is all very clever.   

>by the BIOS POST process - and some of the BIOS code
>runs without RAM for storage, and variables are stored
>in CPU internal registers.
>
>If the BIOS is unhappy with what it reads in the SPD table,
>it will "beep". And occasionally a poster will post a question
>about a BIOS that is beeping, when it should not. And in some
>cases, it tries to match fields in the SPD that are
>"don't cares". That means poorly prepared SPD table
>contents, can result in surprises for users. One DIMM even
>had the wrong SPD chip soldered to it :-) Clever.

LOL   Thanks. 

>    Paul