I'm running memtest on an older computer with the following specs:

Pentium 4 2.53 GHz
1 x DDR-333 256 MiB single-sided (old)
1 x DDR-400 1 GiB double-sided (new)
Intel 845-based chipset

Memtest is reporting the memory is running at a lousey 1060 MB/s. Even considering the age of the computer, that sounds very low. I'm wondering, considering the hardware, is that in fact low? Also, could it be resolved by removing that older DDR-333 stick? What figures should I see knowing that the original stick is PC2700?

I think that is going to be dependent on the efficency of the memory controller and how the the memory bus clock is lining up with the system bus clock. Theorectically PC2700 should be giving you 2700 MB/s.

Looking at Intel's documentation on 845, it looks like they are 100/133 MHz (DDR-200 or DDR-233) which is PC1600 and PC2100, respectively. Could a single-sided stick + a double-sided stick really cause almost (if not exactly considering DDR-233 performance) a 50% loss in performance though?

FordGT90Concept said:

I don't know you've got me on that one. Try running the test with each stick individually.

What speed is the ram acctually running at (CPU-z will tell you)?

Memtest says the FSB is at 131-132 MHz. So it is running at DDR-266 spec. It has been running memtest for over 10 hours and only got 15 passes done. I haven't seen the bandwidth go any higher than 1066 MiB/s.


Edit: I took the 256 MiB stick out and the bandwidth climbed to a lousey 1084 MB/s. Maybe this stick of memory is just too dense for the memory controller?


Edit: Edit: With just the 256 MiB stick in, the bandwidth reports at 1074 MiB/s. That still seems extremely low for PC2100.

64-bit (4 bytes) * 266 MT/s = 1064 MB/s

I think those speeds are actually correct for PC2100. The 2100 MB/s spec must be for dual channel mode.