- Joined
- Nov 28, 2001
- Location
- in a magical field
OK, I have been reading the various posts about the Kingmax PC2700 for the last week. I ordered some from CrazyPC over the weekend which are supposedly "-05" marking, I will see tomorrow and update this post when I read the markings.
After seeing f155's new topic I became a tad concerned and decided to do some more digging. We can see here on the Kingmax site the various DDR modules (just scroll down.) Scanning the part numbers this is what I find:
First two characters="MP" for all 184-pin (non-registered or non-ECC, I assume) modules.
Third character="D" for 266MHz modules; "L" for 300MHz modules. There is no listing for 333MHz modules (PC2700) which I find odd.
Fourth and fifth characters="A8" for 128MB modules; "B6" for 256MB modules.
There are two ending sequences: "2D-683" (which only appears on the first two listings) and "2D-68KX2" (all others.) I am not sure what the difference is here, as all the 266MHz modules (regardless of the end sequence) are listed as 133MHz DDR 7.5ns CL=2.5 in their .pdf datasheets. All 300 MHz modules (which only have the "2D-68KX2" marking) are listed as 150MHz DDR 6.6ns CL=2.5. Again, no listing of 333MHz modules. Also, in the first paragraph, it says the 300MHz modules have three decoupling capacitors (whatever that is
) in parallel for each DRAM, while the 266MHz modules have only two. I am sure you could see these if you looked on the module PCB as SMT devices. This is regardless of ending sequence.
Combined with Flu!d's post from another thread that I will quote:
So, clearly there are differences in the markings between the true 333MHz modules and the others. 1) The third character for the 333MHz (at least the ones fluid has) is "M." Anyone else see a pattern? 300MHz="L", 333MHz="M." Simple alphabetic progression. 2) The chips end in "-05." As for the rest of the chip markings I have no idea, as none of the .pdf's go into that.
To sum up, I am convinced that a marking of MPM indicates a true 333MHz module, while MPL indicates a 300MHz module. As for the "-05" on the end there is no conclusive evidence that I can find. As I said elsewhere, unless someone here is a Kingmax engineer, we cannot truly prove that -7a is not designed for 333MHz. It may just be a production run change or something. The numbers may or may not correspond to a ns rating, even if other RAM types do. I know we like to think it does, and usually it does, but I am trying to do a scientific-type proof here, and not "guess" at anything (not to diss anyone else here...)
Anyway, it would be helpful if f155 would post what his sticker and DRAMs have written on them. And if anyone else has Kingmax DDR of any speed, feel free to post your module sticker/DRAM silkscreens so we can have more evidence.
Sincerely,
MadMan
After seeing f155's new topic I became a tad concerned and decided to do some more digging. We can see here on the Kingmax site the various DDR modules (just scroll down.) Scanning the part numbers this is what I find:
First two characters="MP" for all 184-pin (non-registered or non-ECC, I assume) modules.
Third character="D" for 266MHz modules; "L" for 300MHz modules. There is no listing for 333MHz modules (PC2700) which I find odd.
Fourth and fifth characters="A8" for 128MB modules; "B6" for 256MB modules.
There are two ending sequences: "2D-683" (which only appears on the first two listings) and "2D-68KX2" (all others.) I am not sure what the difference is here, as all the 266MHz modules (regardless of the end sequence) are listed as 133MHz DDR 7.5ns CL=2.5 in their .pdf datasheets. All 300 MHz modules (which only have the "2D-68KX2" marking) are listed as 150MHz DDR 6.6ns CL=2.5. Again, no listing of 333MHz modules. Also, in the first paragraph, it says the 300MHz modules have three decoupling capacitors (whatever that is
) in parallel for each DRAM, while the 266MHz modules have only two. I am sure you could see these if you looked on the module PCB as SMT devices. This is regardless of ending sequence.Combined with Flu!d's post from another thread that I will quote:
So, clearly there are differences in the markings between the true 333MHz modules and the others. 1) The third character for the 333MHz (at least the ones fluid has) is "M." Anyone else see a pattern? 300MHz="L", 333MHz="M." Simple alphabetic progression. 2) The chips end in "-05." As for the rest of the chip markings I have no idea, as none of the .pdf's go into that.
To sum up, I am convinced that a marking of MPM indicates a true 333MHz module, while MPL indicates a 300MHz module. As for the "-05" on the end there is no conclusive evidence that I can find. As I said elsewhere, unless someone here is a Kingmax engineer, we cannot truly prove that -7a is not designed for 333MHz. It may just be a production run change or something. The numbers may or may not correspond to a ns rating, even if other RAM types do. I know we like to think it does, and usually it does, but I am trying to do a scientific-type proof here, and not "guess" at anything (not to diss anyone else here...)
Anyway, it would be helpful if f155 would post what his sticker and DRAMs have written on them. And if anyone else has Kingmax DDR of any speed, feel free to post your module sticker/DRAM silkscreens so we can have more evidence.
Sincerely,
MadMan
WTF??? 
