# Incorrect memory bandwidth ?



## chaotic_uk (Mar 27, 2010)

why has the memory bandwidth dropped from 76.8 to 75 ?


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## blkhogan (Mar 27, 2010)

Thats about normal. I have my 5770 clocked a little over yours and mine isnt much higher.


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## chaotic_uk (Mar 27, 2010)

it has only dropped with the latest version , when i change the memory to 1250 the bandwidth was 80.0gb/s but @ stock it has always read 76.8


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## W1zzard (Mar 27, 2010)

see the changelogs


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## chaotic_uk (Mar 27, 2010)

why the change ? , it has always read gb/s has it not ? . so your readings are differant to ati's , is the change cause of the gtx4** series ?


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## W1zzard (Mar 27, 2010)

it has labeled it GB/s but calculated GiB/s .. now it calculates what it claims

before: wrong, now: right .. now: lower ... would you prefer to see the wrong number?


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## W1zzard (Mar 27, 2010)

actually .. is the number still too high ?

1200 mhz are 1,200,000 hz * 128 bit = 153,600,00 bits per second * 4 (gddr5) = 614,400,000 bits per second / 8 (bits per byte) = 76,800,000 bytes / 1024 (mbytes) = 75,000 / 1024 (gbytes) = 73.242

anything wrong with that ?


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## chaotic_uk (Mar 27, 2010)

no but why do ati claim 76.8gb/s , it says this amount in the hardware info in ccc


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## W1zzard (Mar 27, 2010)

they divide by 1,000,000,000


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## chaotic_uk (Mar 27, 2010)

so it's like harddrives then , ah i see now


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## skylamer (Mar 27, 2010)

:d)


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## dr emulator (madmax) (Mar 27, 2010)

if i where you boss i would just say it's more accurate now where people download it from 
so you won't have to do all the explaining over and over, just my two cents


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