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I just acquired some SDRAM, and from looking at the manufacturer's website, I've determined that it has a latency of 7ns (the last digit is a "-7"). This RAM has been represented as being PC133, and I'm not sure if this is actually the case -- none of the other markings on the modules give me any clues.

Can any of the big giant heads help me out here? I've checked it out using my Google-fu, and my results so far are generally "yes, it's PC133". It seems to work so far in 133 MHz FSB system.

Alternatively, is there a way to see if the memory is working properly in-system?

Pop it in by itself, boot up Memtest and leave it running overnight. If there's no errors when you come back, it'll almost surely work just fine.

It should also tell you what speed the RAM is running at.

If it fits in your motherboard, it ought to function acceptably.
From there, it's easy to use software to determine the actual specifications.

SCRawl wrote:I just acquired some SDRAM, and from looking at the manufacturer's website, I've determined that it has a latency of 7ns (the last digit is a "-7"). This RAM has been represented as being PC133, and I'm not sure if this is actually the case -- none of the other markings on the modules give me any clues.

Considering that PC133 is the final spec of non-DDR RAM and that type of RAM is a technological antique by now its unlikely that buying it from a vendor would be anything but PC133. Considering that it fits into your motherboard, the only other options are PC100 and PC66 (IIRC, its been a while...), and I kinda doubt that they would still be sold since PC133 can work in those scenarios as well (for compatibility reasons).

As far as markings go, it really depends from who you get it. I have a notebook RAM stick here which simply states 64mb and the voltage it works on, nothing else (its non-DDR as well, from a older laptop).

mmar wrote:

SCRawl wrote:I just acquired some SDRAM, and from looking at the manufacturer's website, I've determined that it has a latency of 7ns (the last digit is a "-7"). This RAM has been represented as being PC133, and I'm not sure if this is actually the case -- none of the other markings on the modules give me any clues.

Considering that PC133 is the final spec of non-DDR RAM and that type of RAM is a technological antique by now its unlikely that buying it from a vendor would be anything but PC133. Considering that it fits into your motherboard, the only other options are PC100 and PC66 (IIRC, its been a while...), and I kinda doubt that they would still be sold since PC133 can work in those scenarios as well (for compatibility reasons).

As far as markings go, it really depends from who you get it. I have a notebook RAM stick here which simply states 64mb and the voltage it works on, nothing else (its non-DDR as well, from a older laptop).

I bought it on eBay -- the markings to which I referred were on the chips themselves, not on the module. As I said, I did a bit of Googling, and found that the -7 from this make of chips indicates 7ns latency, which *should* indicate PC133. This did not agree with the stickers on two of the modules which said that it was PC100.

Anyways, I ran memtest, and after six sets of tests there were zero errors, and since the MB didn't just gear down to 100 MHz (the CPU still clocked in at 930 MHz, close enough to the indicated 933) I'm inclined to believe that these will function as PC133.

Thanks for your help, folks.

Some quick math tells me that the memory can function (theoretically) up to 142 MHz (give or take), but since you can't clock your memory at the speed, you have to go to the next highest -- 133MHz. This assumes that each chip on the stick is within a certain tolerance (I could calculate it, but I'm too lazy right now). The capacitance of each bit has the biggest effect on the latency, so the tolerances of the capacitors for the specific manufacturing process may tell you why this particular model is branded as PC100 instead of PC133.