Does upping the fsb cause an unlocked AGP to become unstable?

bupkus

Diamond Member
Nov 25, 2000
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Does upping the fsb cause an unlocked AGP to become unstable?

I want to install a unlocked AXP 2100+ default(266) into a Biostar 210V SFF. I'm told this board has neither an AGP lock nor a cpu voltage mod in the bios.
I suppose if I oc the fsb by 25% the 33 pci will boost to 41.25 and a 66 agp will boost to 82.5mhz.
Is this a 'deal killer'? ie. will it create an unstable system?

Planning to use the onboard video and a pci phone modem.


 

pudds

Member
Nov 3, 2004
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Its possible as there running out of spec although before locks that was the way people overclocked.
 

Cvolt

Member
Dec 23, 2004
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I think it's worth a try. Several years ago I overclocked the Abit BH6 using a Celeron 533, overclocked to 800 by raising the bus from 66 to 100. As you know this overclocks the AGP bus as well, but I didn't have any problems. I believe the AGP bus speed ratio was set at 2/3. The onboard video may be a problem, and is something I don't have experience with.
 

o1die

Diamond Member
Jul 8, 2001
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I've had problems running some athlons at anything above 143 fsb without the agp/pci lock. You'll be lucky if you can reach 150 without errors.
 

Rand

Lifer
Oct 11, 1999
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Originally posted by: bupkus
I wonder why Biostar lists the 210V as a 400 able system?
Link to Biostar

Why wouldn't they?
The KM400A chipset fully supports the 400MHz FSB.

If your AXP is stable on a 333MHz FSB then you can use that without pushing the PCI/AGP bus out of spec, and the board does offer a 1/5 PCI divider and a 2/5 AGP divider.
Between 266 (133DDR) and 333 (166 DDR) you'll have to rely on the 1/4 PCI divider and the 2/3 AGP divider though, which will push the PCI/AGP bus.

Generally your safe with a PCI bus speed around 37-38MHz. Safe AGP bus speeds can vary dramatically depending upon the graphics card used... not sure off hand how the integrated KM400A graphics handles out of spec AGP bus speeds.