FRIHOSTFORUMSFAQTOSBLOGSDIRECTORY
You are invited to Log in or Register a Frihost Account!

Memory bandwidth efficiency

 


Naif
Two days back I replaced a single 256 MB Hynix module(DDR400) and bought two 256 MB transcend modules(DDR 400). SiSoftware Sandra reports their estimated efficiency to be 71% to 73% when they are run in accelerated mode(enabled this from the bios). Where as when the memory acceleration mode is disabled, the efficiency is only 65%. Where as the previous module I owned, even though it was a Hynix yet it had an efficiency of 85%. Add to that, it didnt run in dual channel mode where as these two are running in it. Does anyone here know what the reason could be? I read many reviews that Transcend modules perform better than their Hynix counterparts and thats why I opted to replace my earlier module with two transcend... By the way, I have a P4 2.8 GHz Northwood processor, FSB:800 MHz, sitting on top of an ASUS P4P800(Intel 865PE chipset). Hoping to read some informative replies.
Donutey
the efficiency is reduced when you run RAM in dual channel mode... however your still getting much higher performance than single channel RAM you had earlier. In SiSoftSandra look at the MB/s as an indication of performance.
Naif
Thanks for the reply Donutey. If I recall correctly, your the person who had started an overclocking thread on this forum(correct me if I am wrong). Anyways, do you think there is any way I can increase the performance of my RAM? I am thinking of lowering the CAS# latency. Its default value is 2.5. But I am not sure if I will see any noteble difference by doing so.

PS: I dont want to increase the FSB
Naif
I tried playing around with the timings and here are my results:

At default values, i.e. CAS#: 2.5, RAS# Precharge: 3, RAS# to CAS#: 3, DRAM Precharge: 8, DRam Burst Length:8, this is what SiSoftware Sandra reports

Int Buff'd: 4464 MB/s
Float Buff'd: 4517 MB/s

When I lower down the CAS# to 2.0, DRAM Precharge to 5 and DRAM Burst length to 4, this is what I am getting

Int Buff'd: 4631 MB/s
Float Buff'd: 4628 MB/s

There is a difference but its quite subtle.
Reply to topic    Frihost Forum Index -> Computers -> Software

FRIHOST HOME | FAQ | TOS | ABOUT US | CONTACT US | SITE MAP
© 2005-2007 Frihost, forums powered by phpBB.