Is my ram damaged?

I have a gig of ram installed in the expansion slot for my dell inspiron 2200. There were no problems for the first 3/4 month, but now I am getting blue screens during memory intensive tasks. Removing the memory solves all the problems but I don't know if I should buy a new module or not.

Is it normal for ram to become faulty halfway?

(cont.)

onboad memory: DELL 256 DDR SDRAM 333mhz
expansion memory BUFFALO 1 gig  DDR SDRAM 333mhz


(In Linux the OS will freeze during the task.
When running Windows Memory Diagnostic the output on the screen goes out of place)

memtest86+

Yes, memory can fail over time.  Heat is a major factor.

And are you saying that you couldn't remove the 256 MB DIMM if you wanted to?  Fail.

if u cant remove the primary slot thats retarded. problems can occur with different types and speeds of memory. 2 256's are always going to be more effecient and reliable then an equal mismatched pair.