RAM Details

Hey Kids,

Just got my Akai EXM-128 RAM form Turnkey in London, UK.
Cost me £89. Don't know if that's good or not but I got fed up waiting to see if anyone had got some generic RAM to work.

Anyway, someone said if they knew what was printed on the chips it might help them to figure out what type of RAM it is,
So...

The four main chips are printed as follows:

Hynix 338A
HY57V561620BT-H
KOREA

Now hopefully some of you techie geeks can translate that into a working memory spec. for everyone else!

Hope that helps,
All the best,

Spud

well after reviewing the info that you you put on the thread,
I have came up with one observation:
it was probobly made in Korea...LOL
but thanks, hopefully someone will be able to use this info.

http://search.yahoo.com/search?p=HY57V5 ... fl=0&x=wrt

http://www.google.com/search?hl=en&ie=U ... gle+Search

Thanks for the info.

hamiltone.co.uk appears to have them for £17.63!

Well, Hynix Semiconductor is one of the world's largest producer of computer memory chips, and HY57V561620BT-H would be the part number for the EXM128.

A quick Google search on "HY57V561620BT-H" indicates that it is a 168-pin PC100 Unbuffered SDRAM chip with SPD (serial presence detect). SPD is used to provide the OS with information about the RAM chip's size, speed and voltage. If the OS (in our case the OS of the 1000) doesn't find the SPD info when it boots, it won't detect the RAM properly. This could be why the other 168-pin chips that people tried haven't worked.

I don't know enough about the data that can be provided via SPD to be able to say whether any 128mb 168-pin PC100 SDRAM chip with SPD would work...it might just be that the best solution is to find that exact Hynix part without Akai branding on the cheap.

Edit: SPD is a pretty common feature in the RAM shipped with brand name computers...it may be that it can be used to limit the use of the RAM.

Or you could just follow the Tutor's suggestion :)

thanks to spud for such a generous thing.

make mine a chip buttie.

Rob

any one tested it yet.

Hey,

From earlier posts on this forum I thought we'd decided this thing was lap-top RAM sized, I think that's 144 pin isn't it? It's got to be that size! That ram MPC tutor suggested is 168 pin - wrong size!

Hmmm....

Sorry, couldnt be bothered to count all the pins, it looks much smaller than the ram in my pc anyway. One of my Earlier posts has a link to the picture of the ram on the Jap Akai site - you'll have to search for it, it's in one of the earlier threads on RAM

Easy,
Spud

this is how it looks like
http://www.univers-sons.fr/us2K/exec/product?prod=EXM128

This info is from the data sheet from Hynix Memory Corporation. Which is: http://www.hynix.com

You can download the SDRAM part number decoder from there in PDF. Here is what I got. The part number has been decoded and is underneath its meaning. If someone else has the time maybe they can check my results:

HY__57__V__56__16__2__0__B__T-H

--Hynix Memory--
HY : Hynix Memory

--Product Family--
57 : SDRAM

--Process & Power Supply--
V : VDD=3.3V & VDDQ=3.3v

--Density & Refresh--
56 : 256M 8k Refresh

--Organization--
16 : x16

--No of Banks--
2 : 4 Banks

--Interface--
0 : LVTTL

--Die Generation--
B : 3rd Generation (Ichon) Factory?

--Package Type--
T : TSOP

--SPEED--
H : PC133, CL3

Also from a PDF data sheet for the part number HY57V561620BT-H

Clock Freq: 133MHz
Organization: 4Banksx4MBx16
Interface: LVTTL
Package: 400mil 54pin TSOP2 (TSOP is surface mount)

Sorry for more posts...left out something important:

256M is 256Mbits so there should be 4 of these chips on the EXM128. You divide the 256/8 to get bytes.

4 banks of 32Mb for 128MB ram

Great piece of work sumedho So let me clear up some things we are looking for sodimm config 144 pin 133 Mhz with 4 packages. Am I correct in thinking the Hynix part number refers to the chip itself? In looking at the Hynix web site I would think the module would part out to be something else here is the page [url]http://www.hynix.com/eng/products/module/down/SDRMODULE.pdf

Rob[/url]