RAM upgrade, PC restarts at bootup

[Seasoned]

Hello people,

My sister has a Toshiba satellite a300 which I am using now. When she was using it, she had problems with it freezing all the time and she thought it was due to over heating in the computer. I concluded otherwise when I used it for sometime because it didn't use to freeze that much when I used it and I could use it for longer periods without a problem. Turns out she opens too many applications that eat up the ram and I don't. This baffles me also because the ram(2gb) is ok to handle an operating system like win7 which she was using without a problem, unless it was faulty. So I upgraded to win8 since I read it takes less ram than win7. I used it with less problems but anytime she uses it with all those many applications she opens, it freezes. Thus I decided to upgrade the ram to 3gb(adding an extra gb) and it worked fine for sometime but then it restarted and kept on restarting. Problem is each ram card works fine when used independently but only restarts when used together. I am approaching my exams week and I am getting a bit frustrated by this problem. Any help would be gladly welcomed.

Thanks!!

 

[Tmagic650]

How many memory sockets are there? if there are 2, you probably need to use 2-2GB DDR2 PC667 modules for 4GB total... Not 3GB total

 

[Seasoned]

Thanks for the reply Tmagic. Yes, there are two sockets and both rams are DDR2 but as for the modules I have no idea what they are. Are you saying that in effect, I can't combine 1gb and 2gb ram on my pc? And the only way for me to upgrade is to get an extra 2gb ram?

 

[Tmagic650]

The Ram modules have to both be the same type and speed. There is a label on the modules. Can you provide the numbers on them? Again, they should be DDR2 800MHz types. Some laptops are more sensitive as to the type of memory installed in them

 

[Seasoned]

Oh I see. Anyway there are quite some numbers on both modules. Here they are.
Both DDR2, but I wouldn't know whether they are 800MHz or not.

Transcend (DDR2, 2Gb)
221293-6839
RoHS [69]
JM667QSU-2G-E

Samsung(DDR2, 1Gb)
M470T2953EZ3-CE6
0715
PC2-5300S-555-12-E3
IEC S/N:RMD100JBVG15ZI
PN:1GB 667MHz
SPS:V000100440

I don't know exactly what information you want, so I included all the information on the labels of the modules.
Thanks again.

 

[Tmagic650]

So what was the original memory installed? The Trancend?

 

[Seasoned]

Yes, the trancend.

 

[Tmagic650]

The only thing I can suggest is to buy another 2GB DDR2 667 memory module and replace the 1GB module

 

[Seasoned]

Thanks!