Thinkpads Forum

Hi there,

I'm looking to upgrade ram for X60 and that will be 200-Pin DDR2 SO-DIMM DDR2 667 (PC2 5300). However, there's a lot of ram
out there i.e. A-DATA, Kingston, Crucial, Corsair, PNY etc.
I was wondering is there any different among all those brand or
they are all about the same in term of quality, warantee etc.

Thank you,

Paul

From my perspective as a memory test engineer, I'll have to say that the cheaper memory is usually fine but certain cost-cutting techniques have probably been used. Module assemblers such as A-Data, PNY, Kingston, Corsair (and others) simply buy DRAM on the open market and mount them onto a circuit board. Depending upon the product flow, those finished modules may get some sort of "final test". That testing can be as simple as checking to see if there are any opens or shorts in the pin connections of the module or fairly complex test patterns to check each and every bit of storage. An open/short test can be executed in a few seconds using a dedicated module tester. Depending upon the nature of the test pattern, it can easily take several minutes for something as small as a 256MB module. The adage, "time is money" applies here. The longer that a module requires testing, the more it costs the manufacturer. I would assume that most such module houses rely upon the maker of the DRAM to perform the exhaustive testing of the individual parts and just do a simple test after they have been put on the module.

The design of the printed circuit board used can also have an impact on cost. Better designs have four, maybe even six layers of traces. Power supply decoupling capacitors which are used to "smooth" out the voltage spikes can also play a role in the cost, simply by including few of those components on the board. This can have an impact in the functional performance of the module if the module is installed in a system which does not have a "clean" power supply level.

Testing the modules when installed in the system is usually good enough to determine if it works or not. My recommendation is to use something like memtest86+ and run it long enough to get three complete passes. Semiconductor memory is generally stable enough in that if it works fine today, then it should be working for the life of the system it's installed in.

Warranties can also be a little misleading. A "lifetime guarantee" means nothing if the company goes out of business or requires that you submit the module back to the point of sale. For example, if you buy the module off of eBay you may not be able to send the module directly back to the manufacturer if you have a problem with it. They might require you to take it back to the "retail store" so that it can be properly returned/replaced. Certainly, buying directly from an online or brick-and-mortar store is safer in that respect (you have a dated receipt and proof of purchase), just be sure to read all of the fine print.

I believe with the exception of A-Data, I've used modules from every other maker in your list and have only had a problem with a Micron module (Crucial is owned by Micron and mostly uses Micron parts).

The short advice: not matter who/what you buy, make sure that the seller will accept a return if the module fails to a diagnostic like memtest86+.

Those are words of wisdom(and true experience). I couldn't have said it better. Thanks rkawakami!

I have tried memtest86+ and once did a test that last for two weeks long before I manually stopped it. It seems after the first three hours of testing, the program simply does a write-in-read-out test on every memory block by using random string patterns, which could probably last forever.


teetee

I'm pretty sure that memtest86+ will execute forever if you don't manually stop it. When started, it begins a series of tests which have been deemed the most useful in catching various type of manufacturing defects. The current version (2.01) runs eight different "test patterns" through the full range of memory. A complete pass is when testing finishes Test #8 and the "Pass" counter increments. Most of the default tests are variations on what's called a Moving Inversion pattern.

Not so briefly, it's a sequence where the entire memory is filled with the same data (say, zeros) and then you go to each memory location one at a time and read the data (zeros) and immediately write the opposite data (in this case, ones) at that address. You proceed in this "read data, write opposite data" mode until you've hit all of the addresses in memory. At that point in time, the entire memory has been changed to ones. The pattern then runs the inverse read/write sequence where it reads ones and writes zeros. When it's done with that, it has effectively tested all memory cells for storing both zero and one. But that's not the end of it. It repeats this entire sequence I've detailed so far using the next address signal as the least significant bit. So essentially, the first addressing pass goes like this:

0,1,2,3,4,5,..... and the next addressing pass goes like: 0,2,4,6,8,10,..... and continues with: 0,4,8,16,20,24,...... then 0,8,16,24,32,40,..... and so on.

Which sort of explains why memtest86+ takes about 90 minutes to complete all 8 tests for 1024MB of PC133 memory.

Thanks Ray,
that was most informative!

Hi Ray, thanks so much for a very throughout suggestion.
That's far beyond my expection, as always from you.
I appreciate.

Great timing, Ray and OP.

I am getting ready to upgrade my T43-2687 to 2GB RAM (2x1GB) from 512MB. I've elected to install PC5300 memory (as opposed to PC4200) for the added stability that has been mentioned in several threads on this forum.

FWIW, I can certainly vouch for Micron's reliability...with respect to the PCs they manufactured back in the late '90s. My old 500MHz P3 -- and its original 12GB drive -- are still chugging along 9 years later! Looking back, I am somewhat saddened by their decision to get out of the PC business to focus mainly on memory products.

Ray - How much time should it run MemTest86+ for a 2 X 2G Stick of RAM to be satisfied that the memory is good / bug free?

How many passes?

PS: How is simpletech 2 x 2G RAM for the T61?

Can't tell you an exact amount of time, but I'd allow at least three complete passes to the memtest86+ diagnostic. For a comparison, a T23 with a 1.13Ghz or 1.2Ghz CPU takes about 45 minutes for a 512MB module to go through all of the default tests (one pass). 1024MB takes twice as long. A system with a faster front-side bus speed will take a comparatively shorter amount of time for each pass. The reason for performing at least three passes is that it allows the memory to heat up to probably the highest temperature it will normally see in regular use. Generally, high temp is a DRAM's worst operating point. Refresh needs to be performed more often and access times are slower. However, the opposite end of the temperature spectrum (i.e., cold) can also be a problem too.

I'd also say that as long as you have some sort of DOA guarantee when you first receive the memory and are able to get it to pass memtest86+ without any problems, then you should be okay no matter who the manufacturer is. SimpleTech is a module builder. They don't make the memory components.

I just ran the default Boot CD of Memtest86+ v2.01 on
2 X 2G Sticks of SimpleTech SVM-53SDR2/ 2GB installed in a T61 8992 02U

This is what it shows on screen.

Is this good enough? Something wrong? Should I also do a Burn in for

CPU,
Video Card,
Motherboard,
HDD,
DVD-RW Drive
Wireless & Network card

Some kind of S/W Toolkit to check on all of the above?

Looks like all 4GB was recognized (as depicted in the "Memory" and "Cached" lines). Six total passes were run on the standard tests with zero errors. I'd say that's good enough.

Getting a little off topic... As far as testing/burning-in the other hardware, I'd go with PC Doctor for DOS:

http://www-307.ibm.com/pc/support/site. ... MIGR-67910

The main reasons I prefer the DOS version of PC Doctor, or any other type of hardware diagnostic program, is that:

- you don't need an operating system (XP, Vista, Linux, etc.) or a hard drive to run it; boots from a CD or diskettes
- any possible interference from an OS is eliminated

PC Doctor is able to do comprehensive tests (as far as I know) on the first four items in your list. However, a dedicated HD diagnostic is generally more useful. Hitachi Drive Fitness Test (DFT) and Seagate's SeaTools are examples. PC Doctor does have a test which reads data from optical media but does not test writing. To completely test optical drives I use a program called DVDInfoPro, along with homemade test disks. This program runs under Windows. Those test disks have been previously burned completely full and verified that they read all sectors without any errors. I then run the CRC test in DVDInfoPro and all types of media that it is supposed to support (CD, CD-R, CD-RW, DVD, DVD+R, DVD-R, DVD-RAM, etc). I also burn some disks, generally CD-RW and DVD+RW) and verify them using Easy CD Creator or Nero. For the wireless and network cards it's basically hook them up and see if they can transfer data. PC Doctor does have some simple tests which support the factory wireless card(s) and ethernet, however I rely upon a successful connection to my wireless access point and the ability to launch a browser.

rkawakami wrote:Looks like all 4GB was recognized (as depicted in the "Memory" and "Cached" lines). Six total passes were run on the standard tests with zero errors. I'd say that's good enough.

Getting a little off topic... As far as testing/burning-in the other hardware, I'd go with PC Doctor for DOS:

http://www-307.ibm.com/pc/support/site. ... MIGR-67910

The main reasons I prefer the DOS version of PC Doctor, or any other type of hardware diagnostic program, is that:

- you don't need an operating system (XP, Vista, Linux, etc.) or a hard drive to run it; boots from a CD or diskettes
- any possible interference from an OS is eliminated

PC Doctor is able to do comprehensive tests (as far as I know) on the first four items in your list. However, a dedicated HD diagnostic is generally more useful. Hitachi Drive Fitness Test (DFT) and Seagate's SeaTools are examples. PC Doctor does have a test which reads data from optical media but does not test writing. To completely test optical drives I use a program called DVDInfoPro, along with homemade test disks. This program runs under Windows. Those test disks have been previously burned completely full and verified that they read all sectors without any errors. I then run the CRC test in DVDInfoPro and all types of media that it is supposed to support (CD, CD-R, CD-RW, DVD, DVD+R, DVD-R, DVD-RAM, etc). I also burn some disks, generally CD-RW and DVD+RW) and verify them using Easy CD Creator or Nero. For the wireless and network cards it's basically hook them up and see if they can transfer data. PC Doctor does have some simple tests which support the factory wireless card(s) and ethernet, however I rely upon a successful connection to my wireless access point and the ability to launch a browser.

I am downloading this as we speak but it seems like its Diskettes. Where the hell do I make that happen? ((.

Isnt there a Bootable ISO that I can find somewhere? or Make?