OK, this is the answer I had from the seller.
Because it is high density 128x4 modules.For intel chipset.Must install 128x8 low density.This is the difference.We are expert for the memory
Can anyone make sense of this for me?
Andi.
I will attempt to do so.
DO NOT BUY THAT RAM
High density RAM is extremely incompatible.
Why is it cheap ?
Because the IC's used are rejects/failures.
They should be 8 bits wide but half of the IC is faulty.
Why low compatibility ?
Memory controllers expect to address the memory a certain way 8 bits per IC
A lot of boards will only see half the memory, or none at all
128x4 also needs twice as many chips to make up the module as the chips are only half capacity due to faults.
Power consumption is twice as high as low density because of this.
Another reason they have low compatibility.
Also the memory bandwidth takes a hit because of the 4 bit addressing of the IC's.
If there so bad why do they exist then ?
Because companies building PC's wanted to save money and RAM manufacturers wanted to offload duff IC's.
They should never be on general sale but the less scrupulous traders try to off load them to the general public.
