celeron memory bandwidth

G

Guest

Guest
i've noticed that many celeron motherboards only allow memory to run at 66MHz also, as is the case with my sis630 board. however, memory bandwidth is abysmal at 70MB/s. is this caused by the slow memory frequency or the crappy motherboard? do all celerons with 66MHz RAM configurations perform this poorly?
 
G

Guest

Guest
Yes, they're all that bad. Buy a Duron :)

Seriously, this does sound a bit low, but you can't possibly expect a Celeron to have a similar memory bandwidth to a PIII, which should be at least double. As for the Athlon, it also uses 133MHz memory, bus has a better FSB speed to it can be exploited more efficiently. Even the AMD K6-2 and K6-III have a 100MHz FSB and use 100MHz SDRAM, so they should be a third better at least.

In ideal conditions, the Celeron should have a max memory bandwidth of:

66MHz x 64bit = 4224Mb/s = 528MB/s = 0.5GB/s

The Athlon, in contrast:

200MHz x 64bit = 12800Mb/s = 1600MB/s = 1.6GB/s (approx)

Of course, in practice, these are <b><i>much</i></b> lower, but the multiplying factor (i.e. over three times) should be about the same.

Make sure you're using a good stats program like SisSoft Sandra, and the BIOS settings are correct, e.g. latency, gate a20, syncronous etc. Just reset the BIOS to 'optimal' if you're not sure.
 
G

Guest

Guest
yes, i am using sissoft sandra to get the memory bandwidth of the computer. both the ALU and FPU scores are that low (around 70MB/s). i'm wondering if changing motherboards will work. i'm tempted to blame this sis630 chipset board. i'm thinking of going to the cusl2 instead hoping that will increase performance.

i've gone through the bios, changed the CAS latency and other settings, but at best i can only squeak out 80MB/s, and that's every other time the test is ran. weird system.

it's my first celeron, and my last.
 

FUGGER

Distinguished
Dec 31, 2007
2,490
0
19,780
Comparing Athlon to Celeron, hmmm. ok
You can overclock celeron FSB, and your memory clock will increase with it. Most celerons can hit 100Mhz FSB.
CUSL2 is a great choice for overclocking.
 
G

Guest

Guest
The point I was making is that the scores do look low in Sandra because it compares your chip with a PIII, Athlon and K6-III with 128MB/ECC.