Tek-Tips is the largest IT community on the Internet today!

Members share and learn making Tek-Tips Forums the best source of peer-reviewed technical information on the Internet!

  • Congratulations TouchToneTommy on being selected by the Tek-Tips community for having the most helpful posts in the forums last week. Way to Go!

is ddr sdram compatible? 2

Status
Not open for further replies.

eponymous

ISP
Jul 22, 2004
92
GB
Have just purchased a gigabyte 8ID533 and also have some spare ddr sdram. However, am not sure whether it is compatible?

Also understand that it may work but memory only be recorded at 50% ... if that is the case does it mean memory is also operating at 50% or merely being recorded at 50%?

It would be very helpful to get a clear picture.

Many thanks,
Eponymous
 
From what I've read this board supports PC100 or PC133 SDRAM, not DDR. DDR will not physically fit in the slot. SDRAM is cheap and plentiful, you should have no problem finding some. I've got a bagful...[smile]



Tony

Users helping Users...
 
wahnula - thanks!

You've now got me puzzled and wondering whether the ram that I purchased is what it says it is:

1) Has 168 pins and look identical to sdram
2) Is double-sided (with 8 modules on each side)

A) Sold as "Micron 512 MB 133Mhz SDRAM PC133 DIMM 512MB 168PIN"

When it arrived it had label "512MB PC-133 DDR R36482"

Printed on each module is "48LC64M4A2BTG"

- Digchip.com identifies this as Micron but as 256MB???

B) Sold as "Samsung 256 MB 133Mhz SDRAM PC133 DIMM 256MB 168PIN"

Printed on each module is "K4S280432B"

- Digchip.com identifies this as Samsung but as 128MB?

Help with unravelling what RAM this is would be most helpful?

Many thanks,
Eponymous
 
Best way to tell is visual; Two slots in the connector strip = SDRAM:

256mb-pc133-ecc-sdram-memory-p-n-am23430-am23430.jpg


One slot in the connector strip = DDR or DDR2 RAM:

ddr-ram.jpg


168 pin is also a specification of SDRAM, DDR has 200 pins, so there is no doubt you have SDRAM, regardless what the label says. It could be a stock number used before DDR was born.

As for compatibility, one way to tell: plug it in & boot the system [smile].


Tony

Users helping Users...
 
more information about SDRAM at Wikipedia:


1) Has 168 pins and look identical to sdram
It is SDRAM if it has 168 pins...
2) Is double-sided (with 8 modules on each side)
There are Double Sided modules, just some motherboards do not like Double Sided DIMMs at all, and will thus half the amount on that stick, e.g. 512mb Dimm will get recognized as 256mb... short of buying a new motherboard you will have to live with that...

Digchip.com identifies this as Micron but as 256MB???
Nope, it identifies it as 256Mb (Mega bits)... 16 modules * 256Mb = 4096 Mbits = 512MB (Mega Byte)
same for the Samsung... 16 modules * 128Mb = 2048 Mb = 256MB (Mega Bytes)...

simple math... hope that clears things up a bit...

PS: DDR Ram has a 184 pin connector... DDR2 Ram has 240 Pin...

Ben

"If it works don't fix it! If it doesn't use a sledgehammer..."
 
Wahnula and BadBigBen - many thanks most helpful

This establishes:

- that it is SDRAM and the size stated
- May or may not be fully recognised by the mobo depending on whether it is equipped for double-sided

Currently waiting for the mobo to be shipped so shall have to wait and see.

Another factor I was wondering about ... is high density and double-sided one and the same? ... and, if not, is there a way of checking for high density?? ... plus could this be an additional problem?

Apologies for being so questioning ... Background ... Ram purchased off a large Ebay dealer, who has suddenly withdrawn leaving no opportunity to revisit product information ... which I am now trying to piece together ... and learn about Ram in the process.

Many thanks,
Eponymous
 
If I remember correctly high density is single sided as the memory is more dense in each chip so fewer chips are needed.

The answer is "42"
 
Ben,

I was mistakenly thinking of LAPTOP memory (SODIMMS)...that's where the DDR 200-pin interface enters the picture, from the corners of my aged brain...[smile]

Tony

Users helping Users...
 
Tony,

don't worry... I tend to forget or mix things up myself at times, when you mentioned 200 pins, something in the back of my mind kept going 184 184 184... LOL...

Franklin,

you are partially correct! The memory is denser, but it is not restricted to single sided...

just an excerpt...
First rule, Double sided memory is not always low density modules. High density modules can have 16 chips (8 on each side). 'Standard' RAM chips are organized a DEPTH x 8 Bits. E.g. 32x8, 64x8, etc. That means 8 of the chips make up a 64 bit wide rank (memory bus is 64 bits wide). "Double Sided" is an old term to describe a stick with 16 chips, 8 on each side. And with DEPTH x 8 chips that makes for 2 ranks (or, again in an older style terminology: 2 'banks').
source: High Density memory? Low Density memory?

Epynomous,

is high density and double-sided one and the same?
as you probably read above, no it is not and yet it can be...
and, if not, is there a way of checking for high density??
yes, run the chip number through GOOGLE and it will tell you the manufacturer, there you can look up the statistics on the RAM...
plus could this be an additional problem?
Yes, again some mainboards out there do not like HD RAMs...
Apologies for being so questioning
no need to apologize, to find answers one has to question and hope someone can enlighten them...



Ben

"If it works don't fix it! If it doesn't use a sledgehammer..."
 
Franklin97355, Wahnula, and BigBadBen – Many thanks!

The plot thickens ... not ddr ... double-sided ... now just HD to clarify!

Obtained varying data on each stick …
Beating about in the dark …
Did search on “density” … only registered with Samsung …
Problem is … not quite sure what I’m looking for … or how to interpret it when I find it??
May be the answer lies in the soil ...

Whatever, here is some data, which hopefully might hold some clues???

a) Samsung 256 MB 133Mhz SDRAM PC133 DIMM 256MB 168PIN

M390S1723BT1-C75


•Organization : 16MX72
•Composition : 16MX8 * 9ea
•Used component part # : K4S280832B-TC75
•# of banks in module : 1 Row
•# of banks in component : 4 banks
•Feature : 1,500 mil height & double sided component
•Refresh : 4K/64ms

Module Row density 1 Row of 128MB 20h
Module Row density 1 Row of 256MB 40h
Module Row density 2 Rows of 128MB 20h
Module Row density 2 Rows of 256MB 40h

b) Micron 512 MB 133Mhz SDRAM PC133 DIMM 512MB 168PIN

MT48LC64M4A2 – 16 Meg x 4 x 4 banks


Features
• PC100- and PC133-compliant
• Fully synchronous; all signals registered on positive
edge of system clock
• Internal pipelined operation; column address can be
changed every clock cycle
• Internal banks for hiding row access/precharge
• Programmable burst lengths: 1, 2, 4, 8, or full page
• Auto precharge, includes concurrent auto precharge,
and auto refresh modes
• Self refresh mode
• 64ms, 8,192-cycle refresh
• LVTTL-compatible inputs and outputs
• Single +3.3V ±0.3V power supply

Is any of this information definitive, please?
Does “Fully synchronous; all signals registered on positive
edge of system clock”
suggest both sides will be read … or is that just wishful thinking?

Once again, many thanks,
Eponymous
 
The way I read it,

the Samsung is low density, while the Micron is high density...

Samsung: 16x8
Micron: 16x4


but I would not be concerned until the motherboard arrives and the modules do not work...

Ben

"If it works don't fix it! If it doesn't use a sledgehammer..."
 
I'm reading the Samsung as ECC memory (16MX72) That's 9 bits (8x9) vs. 64 bits (8x8). This type of memory is/was found in older server and high-end workstations. It may not be compatible with non-ECC equipped motherboards.
 
Freestone,

thanks, I missed that one... kudos...

Ben

"If it works don't fix it! If it doesn't use a sledgehammer..."
 
Thank you all for your excellent advice - very informative.

Now the hard bit - wait and see ... patience is not one of my virtues!

Thanks again,
Denis
 
Postscript

Mystery solved. The RAM that I had purchased was bogus. It was cheap, substandard and stamped with brand-name logos together with facsimiles of actual s/ns ... easily fooled the non-cogniscienti, such as me! So Wahnula, if you've still got a bagful... I'm looking for a reliable source of RAM?

Many thanks,
Eponymous1212
 
Status
Not open for further replies.

Part and Inventory Search

Sponsor

Back
Top