• Some users have recently had their accounts hijacked. It seems that the now defunct EVGA forums might have compromised your password there and seems many are using the same PW here. We would suggest you UPDATE YOUR PASSWORD and TURN ON 2FA for your account here to further secure it. None of the compromised accounts had 2FA turned on.
    Once you have enabled 2FA, your account will be updated soon to show a badge, letting other members know that you use 2FA to protect your account. This should be beneficial for everyone that uses FSFT.

trouble explaining 128 bit vs. 256 bit

J

Jaeflash

n00b
Joined
Sep 7, 2004
Messages
20
I'm having trouble explaining to someone why a 9800 128mb/256 bit is better than an 9800 256mb/128bit card. I understand it in my head, but I just can't articulate it into words. Anyone care to lend a hand and explain it out?
 
Mathematics might help.

memory bandwidth = (bit-width x MHz x 2 [DDR]) / 8 [bits -> bytes]

Therefore, with 128-bit memory you have half the memory bandwidth, everything else being equal. Also, DDR2 has higher latency than DDR1, just FYI. More memory is helpful in certain intense situations (high res, AA/AF), assuming the core can keep up and the FPS at those settings is in an acceptable range, although in your scenario the lack of bandwidth would probably remove any advantage even in that rare case.
 
128bit/256bit... thjink of it as a highway... if you ahve a 4 lane highway and you have a throughput of an 8 lane highway system, your system will be clogged all to hell. Now if you have an 8 lane traffic system with 8 lanes of traffic moving through it... it's flowing nice and fine. the 9800 gpu can handle the 8 lanes, don't get anything less.

~Adam
 
the memory interface is essentially how much data (in volume) the GPU has access to in any given cycle. if there is a 128bit bus, it will only be able to get half the data from the memory, hence cutting performance in half
 
You must log in or register to reply here.
Back
Top