Tips on upgrading ram

Just recently i upgraded the ram of my Compaq Presario notebook. There are things that i learned and i want to share these so that others may not commit mistakes in upgrading their ram.

1. Do not mix ram with different cas latency!!!
This is so much important for guys who want to upgrade their ram. i went to the store and bought a 512 sodimms with 3 cas latency. my preinstalled ram, however, has 2.5 cas latency. when i mixed both of them, it did boot but lo and behold it doesn't take 10 mins and my computer will shutdown with blue screen of death (BSOD "hardware stop"). i tried to boot again but it continue to have the same error.

usually sodimms pc 3200 has 3 cas latency but also some has 2.5. just be sure that you look every specs of the memory you are going to buy and compare it with your preinstalled ram (if you have).

by the way pc 3200 and pc 2700 with the same cas latency will work perfecly fine.
2. It is ok to mix different brand of memory.
my preinstalled ram is samsung while my new ram now is kingston. they both help each other to speed up my notebook.

if you have any other tips, just continue posting here.

:centrino: :hp:

 

So here is my question - are these two capable of working together?
Micron Tech
Kingston

 

I'm curious if the CAS thing is really the issue, or if the memory is just bad? I remember when I upgraded the RAM in my Toshiba, I took out all the old RAM, put in new stuff, seemed to work, then rebooted with BSOD, tried some more eventually found this program

http://www.memtest86.com/

Which seems to be a fantastic program, I tested the RAM, and lo and behold it was faulty, returned it to the store, got another stick, tried that and once again, it was faulty, got a third stick (this time I got wise and took my laptop to the store) installed that, and it seemed to work.

Recently the RAM died on me, computer was acting funny, seemed to start BSODing a lot, ran this program, and lo and behold one of the memory sticks was dead.

 

well, if BSOD starts to pop up when you install new ram the problem could include a defective ram. when i installed my new ram the BSOD started to pop up and to be sure i'm not diagnosing problem incorrectly, i took off my old ram and start using the new one. LO and behold it worked fine. But when i mixed it with my old ram with diff cas latency, that Annoying BSOD started to pop up again.

by the way my old ram doesn't have any problem since it worked well by itself.

i tested both ram with microsoft memory diagnostic tools and all of them were fine!

From that i knew it was the cas latency that's giving me headache! (when i changed my ram with same cas latency it worked and still working good! )

Download Microsoft memory diagnostic tools here:
http://www.majorgeeks.com/Microsoft_Windows_Memory_Diagnostic_d3955.html

 

haven't tried mixing Micron Tech and Kingston, but using diff brand should not be a problem.

 

Are the specs right for them to work together?
If I want to get the exact same RAM to be the second one (Micron tech) then from the Fujitsu-Siemens Service they told me a price which was about $180. If I buy the Kingston RAM to be the second one then the overall price would be around $85.

 

Usually (always) when you go to maker of your notebook it will charge you a lot! however, a third party ram cost drammatically low! The advantage on the former is that they have tested the ram specifically to your notebook. but kingston is also reliable!

if you have 512 pc 2700 and wanted to uprade it, you can use pc 3200 but be sure it has the same cas latency (you can mix diff ram speeds and capacity but not diff cas). otherwise, your laptop will either not boot or will BSOD.

also take note that if you have pc 2700 and mix it with pc 3200, your laptop will run in slower speed (i.e., in pc 2700 not pc 3200).

 

by the way check this article, it might help you a lot!

http://www.notebookreview.com/default.asp?newsID=2612

 

Thanks for the article. I have read it already. I guess I'll just have to take the risk and try how these two work together. I don't have any place to buy the Micron Tech. RAM either. Thanks for the replies

 

I have an old notebook which runs on PC2100 and CL=2.5. I paired it with a PC2700 chip that can run PC2700 at CL=2.5 or PC2100 at CL=2. So in a way, I did mix RAM with different CAS Latencies. However, the PC2700 automatically downclocked itself to the lower RAM specs and now both run at PC2100 with CL=2.5. Worked right out of the box and haven't given a single issue.

 

But what about the memory chips on RAM? When I added RAM to my PC I had problems. The new RAM 128MB had 4 chips, the old one 256MB had 16 and 128MB had 8. So in my experience the number of memory chips on RAM does matter. Or on new computers it doesn't matter? The PC was an old Intel with PIII and with PC-133 SDRAM

 

It was probably the same number of chips. Actually all SODIMMS I've seen so far had the same number of chips (4 on each side).

 

For example (found from google with serial KVR333X64SC25/512). There are also pictures of 4 chips on both side too. I don't understand the Kingstons datasheet very well to say if it's a 8 or 16 chip RAM.