How do i select the right RAM?

Do you have a question? Post it now! No Registration Necessary

Translate This Thread From English to

Threaded View
This is an IBM / Lenono T43 laptop. The addon ram card suddenly failed
after many years. Several times in the past year the computer would blue
screen or lockup. Removing that ram card fixed it for awhile. Now its
just dead and Im running the laptop without it. Choosing the right card
seems difficult.

Is there a site that lists them?


How do i choose?


This is what the old dead card reads.
512mb DDR 333 cl2.5
MT16VDDF6464HG-335G2
PC2700S-3533-1-Z
118 pin pc2700 2.5v

Thanks


Re: How do i select the right RAM?
snipped-for-privacy@myshop.com wrote:
Quoted text here. Click to load it

How do you run your laptop without ram?

You have your work cut out for you. https://www.crucial.com/ shows three
types of T43s, all of which use PC2-5300 memory:

https://www.crucial.com/usa/en/compatible-upgrade-for/Lenovo/thinkpad-t43-series -(type-1875)*
https://www.crucial.com/usa/en/compatible-upgrade-for/Lenovo/thinkpad-t43-series -(type-2686)*
https://www.crucial.com/usa/en/compatible-upgrade-for/Lenovo/thinkpad-t43-series -(type-2687)*

Unless Crucial's database is wrong (it's been known to happen) your old  
PC2700S memory is incompatible with your T43 laptop. Incompatible memory
can cause your laptop to blue screen on you or not boot.

Thank you, 73,

--  
Don Kuenz, KB7RPU
There was a young lady named Bright Whose speed was far faster than light;
We've slightly trimmed the long signature. Click to see the full one.
Re: How do i select the right RAM?
On 17/10/2019 15:02, Don Kuenz, KB7RPU wrote:
Quoted text here. Click to load it

It is a bit elderly to bother repairing. Exactly which model of T43?
Are you sure about 118 pin and 2.5v?
Quoted text here. Click to load it

Thinkpad Lenovo say T43s memory spec is:

?PC2-4200 CL4 Non-Parity (NP) Double Data Rate Two (DDR2) Synchronous  
DRAM (SDRAM) SO-DIMM memory
?200-pin SO-DIMM with gold-plated leads
?256 MB, 512 MB, or 1 GB PC2-4200 CL4 NP DDR2 SDRAM SO-DIMM
?Supports up to two 1GB SDRAM SO-DIMMs

from
https://support.lenovo.com/gb/en/solutions/pd012235

I don't think they do *any* valve based RAM.

--  
Regards,
Martin Brown

Re: How do i select the right RAM?
Quoted text here. Click to load it

PC2-4200 and PC2-5300 both belong to the same family. Either module can
be used. Crucial, naturally, sells only the latest evolutionary member  
of the family. For this case Crucial's database is correct.
    Their database is inevitably correct. It only failed me once out of
about a thousand queries. They immediately updated it after the failure
was reported to them.
    Their database can also indicate the feasibility of using a given
memory module. It's a big red flag when they don't sell a particular
module. Although it may not be a show stopper.
    Crucial also provides excellent memory documentation to the public
gratis.  

Thank you, 73,

--  
Don Kuenz, KB7RPU
There was a young lady named Bright Whose speed was far faster than light;
We've slightly trimmed the long signature. Click to see the full one.
Re: How do i select the right RAM?
On 2019/10/17 7:29 a.m., Martin Brown wrote:
Quoted text here. Click to load it
d
lue

rd
ee
t43-series-(type-1875)*  
Quoted text here. Click to load it
t43-series-(type-2686)*  
Quoted text here. Click to load it
t43-series-(type-2687)*  
Quoted text here. Click to load it
d
ry
ronous  
Quoted text here. Click to load it

Wouldn't that be magnetic core memory - for valve based RAM? Magnetic  
bead lattices...tube jukeboxes (Seeburg) used them for memory back in  
the late 50s and right through the 70s.

Here is a how-to:

https://sites.google.com/site/wayneholder/one-bit-ferrite-core-memory

Looks like fun!

John ;-#)#


Re: How do i select the right RAM?
On Thu, 17 Oct 2019 15:29:27 +0100, Martin Brown

Quoted text here. Click to load it

Quoted text here. Click to load it



Quoted text here. Click to load it

These https://en.wikipedia.org/wiki/Williams_tube tube RAMs stored 1-2
kilobits for more than 70 years ago.


Re: How do i select the right RAM?
On 17/10/2019 18:41, snipped-for-privacy@downunder.com wrote:
Quoted text here. Click to load it


There is a working one on a fully operational model of Baby at the  
Manchester Museum of Science and Industry  32 x 32 = 1024 bits

https://www.scienceandindustrymuseum.org.uk/whats-on/meet-baby
https://en.wikipedia.org/wiki/Manchester_Baby

They run it for demos on certain days. Takes a while to warm up.

--  
Regards,
Martin Brown

Re: How do i select the right RAM?
On Thu, 17 Oct 2019 14:02:06 -0000 (UTC), "Don Kuenz, KB7RPU"

Quoted text here. Click to load it
There is 512mb ram built in. You gotta rip the whole laptop apart to get
to it. The card that failed is the easy to access SECOND (addon) card.

Quoted text here. Click to load it

This is a TYPE 2379. Thats not listed

Motherboard Model:
IBM 2379RFU

Quoted text here. Click to load it

That addon card worked for the past 8 years or so. It began acting up
after I slammed on my brakes (deer ran in front of me), and the computer
flew off car seat. Removing that second card fixed it, but it sure is
slow now.

Using HWinfo32. This is what my first card lists as:

-----------------

HWiNFO32 Version 6.10-3880

185AC0F734824A8
-----------------------------------------------------------

 [Current Computer]
 [Operating System]

Memory
--------------------------------------------------------------------

 [General information]
  Total Memory Size:                      512 MBytes
  Total Memory Size [MB]:                 512
 [Current Performance Settings]
  Current Memory Clock:                   166.1 MHz (5 : 3 ratio)
  Current Timing (tCAS-tRCD-tRP-tRAS):    2.5-3-3-7
  Memory Channels Active:                 1

Row: 0 - 512 MB PC2700 DDR-SDRAM Samsung M4 70L6524CU0-CB3
---------------

 [General Module Information]
  Module Number:                          0
  Module Size:                            512 MBytes
  Memory Type:                            DDR-SDRAM
  Error Check/Correction:                 None
  Memory Speed:                           166.7 MHz (PC2700)
  Module Manufacturer:                    Samsung
  Module Part Number:                     M4 70L6524CU0-CB3  
  Module Serial Number:                   871367426
  Module Manufacturing Date:              Year: 2005, Week: 37
 [Module Characteristics]
  Module Width:                           64-bits
  Module Voltage:                         SSTL 2.5V
  SPD Revision:                           1.0
  Number Of Rows:                         2
  Row Address Bits:                       Bank 1: 13, Bank 2: 13
  Column Address Bits:                    Bank 1: 10, Bank 2: 10
  Number Of Banks:                        4
 [Module timing]
  Supported Burst Lengths:                2, 4, 8
  Refresh Rate:                           Reduced 0.5x (7.8 us)
  Min. Back-to-Back Clock Delay:          1
  Supported CAS Latencies (tCAS):         2.5, 2.0
  Min. RAS-to-CAS Delay (tRCD):           18.00 ns
  Min. Row Precharge Time (tRP):          18.00 ns
  Min. RAS Pulse Width (tRAS):            42 ns
  Supported Module Timing at 166.7 MHz:   2.5-3-3-7
  Supported Module Timing at 133.3 MHz:   2.0-3-3-6
  Min. Row-Activate To Row-Activate Delay (tRRD): 12.00 ns
  Supported CS Latency:                   0
  Supported WE

--------------------


Ideally, Id like to find this same card. But thats unlikely. And since
Im replacing it, I may as well get a 1gb card, thus giving me 1.5gb
total ram.

(No, I'm not tearing the whole computer apart to replace the internal
one).


Site Timeline