I am looking to upgrade the memory on my ASUS P4T533 motherboard. Currently I have Samsung RAMBUS 256MB, 32 Bit, 1066MHz, RIMM 4200 (SKU # MD16R1628AF0-CN9DF)in the above motherboard. I am inquiring about the compatibility of Samsung RAMBUS 512MB, 32 Bit, 1066MHz, RIMM 4200 (SKU # MD16R162GDF0) with my current memory. The old Asus website listed the second RIMM 4200 module as qualified memory. My main question is whether or not all RIMM 4200 modules are compatible. Samsung specs lists the tRAC (Row Access Time) as 32 nsec for the above RIMM 4200 modules. Am I wrong or is this the spec that is most important? This spec is the speed of the memory? The cost of 512MB of RIMM 4200 RAMBUS memory is rather high. I don't want to get get stuck with memory that I can't use with my old memory.
I know, I should ditch the RAMBUS based motherboard! But from everything that I read, RAMBUS seemed like the way to go for video editing when I bought the motherboard.
I don't see why they wouldn't be from a first look.
"My main question is whether or not all RIMM 4200 modules are compatible. Samsung specs lists the tRAC (Row Access Time) as 32 nsec for the above RIMM 4200 modules. Am I wrong or is this the spec that is most important?"
I wouldn't be so concerned with the tRAC values between the modules. In answering the next question you will see why.
"This spec is the speed of the memory?"
The tRAC values are based on the speed of the chips. 400MHz(aka PC800) is 40ns and 533MHz (PC1066) is 32ns. They are just ratings just like DDR400 is to PC3200. I haven't seen RIMM4200 modules that aren't 32ns. Look at you module that you have now. <A HREF="http://www.samsung.com/Products/Semiconductor/Support/L..." target="_new">Click here to see how to read your current module.</A> My bet is that your current module is also 32ns.
Your best bet is to contact Samsung Electronics to be 100% sure.
When/if you contact them, also ask if there have been any compatability issues with the P4T533, and if there have been any issue mixing modules.