running agp 66+ MHz

[Jarhead7236]

does the card being overclocked make it more susceptible to problems from the agp being over 66MHz? my 9K Pro didn't have any problems running stock speeds at 70MHz but my 9600Pro (in sig) starts giving me weird stuff...hence, the initial question.

 

[disk11]

For some reason, ATI cards don't like overclocked AGP buses. Nvidia cards handle them very well. I heard stories of people back in the 440bx days overclocking to 133 and the AGP bus was 89 with their Nividia card

Now that I think about it, I remember someone lowering the overclock on their ATI card and getting a better AGP/FSB overclock on their Asus PC-DL (based on the intel 875 chipset and no AGP/PCI lock?WTF??)

 

[Jarhead7236]

well, setting it back to stock speed didn't work so i'm at 214 right now...i really like this kt600 board except for the "small" issue of no agp/pci lock...oh well. i can always runs 210x11.5...

 

[larva]

For some reason, ATI cards don't like overclocked AGP buses. Nvidia cards handle them very well. I heard stories of people back in the 440bx days overclocking to 133 and the AGP bus was 89 with their Nividia card

Bah, that was the Fisher-Price BX configuration. I routinely ran 150fsb (100MHz AGP) with P3B-F BX boards and Geforce256 and GeforceDDR video cards, and Abit BF6s at 160fsb (106.6 AGP). G400 Matrox's stood it fine as well.

 

[johan851]

Hmmm...in response to your question. The card being overclocked probably doesn't effect maximum FSB speed as much as maximum FSB effects the card's maximum overclock. Make sense?

The card's speed probably won't have much effect on how high you can jack up the AGP bus. But a higher AGP bus will make your card a little more shaky at higher overclocks. My 9500 freaks out over 72MHz on the AGP bus. It really sucked, because I couldn't run my FSB faster than 180MHz on my KT400 board. SO glad I got an nForce2 .

 

[Jarhead7236]

yeah, i got my nF2 boards, too...but l like the kt600, too. i'm just gonna accept that anything over 215 is gravy and stay where i am and up the multi...now i just gotta mod this thorton to a barton. thanks for the replies.

 

[violineb]

Does a higher AGP clock rate do anything for performance? Or just allow higher overclocking on boards that don't have an AGP lock? In other words is jacking up the AGP bus useless on let's say a NF2 board?

 

[Yuriman]

I think there imight be a very small gain, but the instability isnt worth it.

 

[voodoomelon]

Ok, i'd steer well clear of the AGP bus if you have ATI.
My Radeon completely messed up in games and it was only 11mhz over the AGP stock. Every single game would hang and crash and restart after a couple of seconds of play.
The thing was, I had no idea what the problem was. I didn't even remember changing the bus speed. I thought it was a driver or hardware problem. I found the problem, changed it back to stock and all was well.

but the instability isnt worth it.

Exactly.

 

[larva]

Does a higher AGP clock rate do anything for performance? Or just allow higher overclocking on boards that don't have an AGP lock? In other words is jacking up the AGP bus useless on let's say a NF2 board?

As mentioned above, elevated AGP/PCI rates do help performance. It is a small difference, but it is a greater factor than say, AGP 8X vs 4X. As established above the primary limitation to how fast you can run them is the video card, and ATI's tend to hate out of spec busses. If benchmark glory is the goal it's always worth a try, but typically it's only going to pan out in a realistically usable fashion when using Intel chipsets and Nvidia video cards.

There are also odd cases where the AGP/PCI lock may be limited. I have heard cases with i875 chipsets where the lock screws up above 300fsb, and higher overclocks depended on disabling it and setting the AGP/PCI slightly out of spec. It just goes to show there is always an exception that prooves the rule, and it generally pays to ignore pre-conceived notions and simply try the alternatives to establish what actually best in your case, rather than be limited by common "knowledge".

 

[Jarhead7236]

i knew it'd be absolutely terrible but i bought a GF4-MX4000 to test the nvidia handling a higher agp (they didn't have any ti cards)...it was this or the fx5200 but i already had one and hated it...anyway, running agp @ 72MHz for now and so far, so good....i wonder if this means a 5700 would do just as well....we'll see in a few weeks...i am kinda kicking myself in the a$$ cause they had 9600se's for under $95...

 

[larva]

If you like nvidia cards I would suggest skipping the 5700 and getting a FX5900se or 5900nu. The EVGA 5900se is only $188 bucks and will smoke a 5700. The 5900nu's are just over $200 these days. While the DX9 shader performance is below that of ATI's, these are solid cards that oc well and are superior in most other respects. I've got a Leadtek 5900nu with VIVO coming I bought as a newegg refurb for $168.75, a price level at which I can accept the compromises inherent in 5900 as I don't play any games new enough to be problematic.

 

[Jarhead7236]

i looked at the 5900's but figure i'll wait for a new high end card til the spring/summer....the mx4000 is handling the higher agp better than my 9600pro...