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BobM
19-01-2004, 09:01 PM
With all other specs. in my P.C. well over what is required to play games does the F.S.B. of the MOB make a difference to the graphic cards performance. ??. What I am really asking is if my mother board has a F.S.B of 266, is it worth buying a graphics board which is capable of using 400

tweak\'e
19-01-2004, 09:54 PM
simply put, graphics cards don't use the fsb. the fsb is more to do with data in and out of the cpu.

JohnD
19-01-2004, 10:15 PM
tweak'e

Are you sure you are right here? As far as I know the only two buses coming out of the CPU are the FSB and the BSB (back side bus to the cache).

Have a look at:

http://www.tomshardware.com/motherboard/20020720/sis648-01.html

BSB not shown in this diagram

tweak\'e
19-01-2004, 10:48 PM
bsb is not really used much these days (i assume your meaning the bus to the l2 cache on the motherboard or slot board)

if you look in that first diagram at tomshardware you will see the fsb or system bus is the only thing coming out of the cpu. the viseo cards connect via the agp bus. changeing fsb speeds dosn't change the agp or video card speeds.

JohnD
19-01-2004, 11:09 PM
> simply put, graphics cards don't use the fsb. the fsb is more to do with data in and out of the cpu

OK - changing the FSB doesn't change the AGP speed but AGP still has to get back to the CPU via the FSB - so I guess the above statement isn't quite true?

tweak\'e
19-01-2004, 11:33 PM
true the agp still has to get back to the cpu via the fsb, hence the "simply put". the fsb can limit the speed of the whole pc. buying a fast video card for a slow pc (weather the pc is slow due to fsb or other is irelavent) is a bit pointless.

BobM
20-01-2004, 09:27 AM
Bear with me guys, firstly I am told that the fsb speed is irrelavent, now I'm told its crucial.??

John Grieve
20-01-2004, 10:12 AM
The FSB is divided down by the AGP controller chip to a speed of 66mhz whether the FSB is 133/266/400. So the AGP card only ever runs at 66mhz anyway on all systems in normal modes.

If you overclock the FSB (to say 430mhz) then the AGP controller still divides the speed the same way so the AGP card will then run at 70-80mhz. New motherboards allow you to lock the AGP speed while overclocking the FSB.

AGP by the way uses the PCI bus (which is 33mhz standard) and multipies it by 2 getting the 66mhz.

So the graphics card while working with dividers on the FSB is locked into using 66mhz (or higher if you overclock the FSB with a natural limit around 80 odd mhz at which the cards usually start to produce errors.)

Changing the vidcard may improve performance if the CPU has spare power still available but ultimately its the CPU speed will limit it. Going to a motherboard with a faster FSB will help performance but not because the cards running faster but because the CPU and busses for it can perform more calculations quicker giving an effective speed boost to performance overall including the framerate in the game.

Hope that helps understand it.

tweak\'e
20-01-2004, 11:26 AM
> if my mother board has a F.S.B of 266, is it worth buying a graphics board which is capable of using 400

>With all other specs. in my P.C. well over what is required to play games

if your pc is well over the specs required and the gamesplay fine and at a good quality and res they is no point in upgradeing your video card.

the FSB dosn't determin the speed of the graphics card. the only thing to really clog the video card is the agp which even at 4x should be fine even with the top end cards. however its not much point buying top end video card if your cpu/ram etc won't let the game run fast enough.

you might get better help if you post what sort of pc/cpu/ram/video card you have and the games you play on it.

BobM
22-01-2004, 11:07 PM
Thanks John and Tweak'e. The paragraph < Going to a motherboard with a faster FSB will help performance but not because the cards running faster but because the CPU and busses for it can perform more calculations quicker giving an effective speed boost to performance overall including the framerate in the game.> says it all as far as my query is concerned however I would like to be given an educated guess as to what board would be optimum price wise for my system as my gaming results are abysmal at the moment with Halo. AMD Athlon 1.9+ 768ddr ram 40gb 7200 hd FX 5200 graphic card

agent
22-01-2004, 11:39 PM
From Australian PC User (Jan 2004):

Using a card based on the Radeon 9800 XT chip, in Halo: Combat Evolved... reportedly, at 1024x768, they only just broke 50 frames per second.

So an FX5200 wil perform abysmally. PC User say to hold out for the next generation of graphics cards, but as per usual, they'll come out expensive, and by the time you get one better technology will both be out, and around the corner.

Have you tried downgrading all the video settings in Halo?