Super Cheap Chinese eBay RAM, help me check it!

everapt

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Apr 23, 2016
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I am looking to purchase 8GB of DDR2-800 ram from a Chinese eBay seller because the price is pretty cheap.

I will say this first, I have purchase cheap Chinese ram before, and it has worked 100% stable without any problems/blue screens for 3+ years, so I know they CAN be legit.

Nonetheless I want to check it's legitimacy so that I can return it if there are any problems.

Is there any program to check if the 8GB capacity of the ram is as advertised? Would something like MemTest86 test for that?

I want to check capacity because I've heard, at least with USB storage drives, that some Chinese sellers sell cheap ones that post 64GB capacity when you plug them in but in reality they have like 16-32GB. And so I'm wondering if it's a similar case with RAM as well.
 

Mega6

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boot computer. write down the amount of ram as A. shutdown. put cheap ram in. boot computer. write down the number as B. Subtract A from B. That is the amount of detected cheap ram.
 

everapt

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Apr 23, 2016
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boot computer. write down the amount of ram as A. shutdown. put cheap ram in. boot computer. write down the number as B. Subtract A from B. That is the amount of detected cheap ram.

I have absolutely no idea what you're talking about...

What am I missing here?
 

Ocellaris

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I have absolutely no idea what you're talking about...

What am I missing here?

Just put in the RAM and see how many GB your system reports. You are overthinking this, RAM isn’t SD cards with wrongly advertised sizes.
 

everapt

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Apr 23, 2016
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Just put in the RAM and see how many GB your system reports. You are overthinking this, RAM isn’t SD cards with wrongly advertised sizes.

I hear you, I was just thinking there has to be some catch, either with capacity or something else... Why are people always so afraid to buy Chinese RAM from eBay?
 

everapt

n00b
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Apr 23, 2016
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The system ram amount is displayed on boot by the BIOS.

I get that, but why am I writing down and subtracting RAM A from RAM B? If I want to know capacity of the cheap RAM, I can just check it in BIOS or Windows, right?
 
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MTDEW

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I think he meant if you were adding to your existing ram you'd need to subtrack A (A = your old/original ram) to get how much you gained from adding the new ram.
 

ChoGGi

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^ likely that, after all he doesn't ever say to remove the old ram :)
If you really want; you could pop out the old stuff and run the chinese stuff through memtest+ (not to check the size, but to see if it's crap or not).
 

cyklondx

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you could always use aida64 to test memory. It will load/unload to the full, multiple times, and benchmark them etc.
 

Spaceninja

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Boot up off of a Linux installer and use Memtest on just that stick of RAM. Check on it in a few hours and if you see errors it is trash, if not it is good.
 

kirbyrj

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It looks like passmark has their own memtest 7.5 which works pretty well on newer chipsets (Ryzen in my case).
 

matt167

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most of that cheap DDR2 ram is made from recycled components and may or may not work on your system due to the way the chips are placed.. If it is marked as " For AMD" or something like that, it's a guarantee that's what it is because the stuff will not work in Intel. I don't remember exactly what is wrong with it, but it's been a few years.
 

Jayy88

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Mar 9, 2018
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Chine has came a long way. I just wouldn't definitely throw money at a ddr2 system in 2018.
 

GiGaBiTe

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If it is marked as " For AMD" or something like that, it's a guarantee that's what it is because the stuff will not work in Intel. I don't remember exactly what is wrong with it, but it's been a few years.

The difference between normal memory modules and Chinese memory modules is the density of the memory chips used.

Most normal PC memory uses low density memory chips, where the width of the memory address rows is lower and the number of columns is higher. An example would be 128Mx16 or 2 megabits.

High density memory changes the layout where the address rows are larger and the columns are lower. An example would be 512Mx4, which is also 2 megabits.

Most memory controllers aren't designed to be able to use high density memory, hence why it has such a low compatibility. High density memory has the best compatibility with AMD systems, and older systems where the memory controller was still on the north bridge. 3rd party chipsets for both Intel and AMD back then generally didn't care about memory organization and would use almost anything. I used to have a couple of VIA and SiS chipset boards which would literally take any kind of memory that fit in the slot. Low density, high density, ECC, buffered. etc. it would use it all.
 

matt167

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The difference between normal memory modules and Chinese memory modules is the density of the memory chips used.

Most normal PC memory uses low density memory chips, where the width of the memory address rows is lower and the number of columns is higher. An example would be 128Mx16 or 2 megabits.

High density memory changes the layout where the address rows are larger and the columns are lower. An example would be 512Mx4, which is also 2 megabits.

Most memory controllers aren't designed to be able to use high density memory, hence why it has such a low compatibility. High density memory has the best compatibility with AMD systems, and older systems where the memory controller was still on the north bridge. 3rd party chipsets for both Intel and AMD back then generally didn't care about memory organization and would use almost anything. I used to have a couple of VIA and SiS chipset boards which would literally take any kind of memory that fit in the slot. Low density, high density, ECC, buffered. etc. it would use it all.

yup, I remember now, thanks for clarifying.. I had bought 6 or so Dell Optiplex 755's and was looking to upgrade ram and flip.. Quickly found the 8gb ram for $10 was junk and would not work, and had read well into it at that time. I ended up doubling the ram on one of them by taking the ram from another and then I put 8gb of decent ram into the ramless box and kept it for myself. Never made much on those computers though.
 
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