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How do I lock the AGP/PCI/IDE bus on A7N8X deluxe?

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mfjonny

Member
Joined
Jan 9, 2003
Location
California
I just switched over from a KT400 board... Can someone tell me how I can lock the AGP/PCI/IDE buses at stock settings so i can overclock my FSB?

Thnx in advance.

-JONNY
 
If you look in the bios, in the section where you alter the FSB, scroll down and you should see the AGP frequency setting. I think default its on auto, but just change it to 66 and that should lock the AGP/PCI bus up nicely.
 
It is auto-locked AFAIK. You need to manually change it to make it higher than stock.
 
When you overclock the FSB it keeps the AGP and PCI cards running at stock speeds. This is helpful as you can only push them so far before you run the risk of corrupting your hard drive. Thus, you can get get higer clock speeds on your FSB which ultimately speeds up your whole system. It's a very nice feature which I wish I had on my other systems.
 
So final verdict: leave it on AUTO and all three, AGP, PCI, and IDE will be locked?

Can anybody second that?
 
It's my understanding that the PCI is locked no matter what the setting. The AGP needs to be locked at 66mhz to be at stock speed. If you set it to auto it will increase by divisors of the FSB as per a normal motherboard.
 
So setting AGP at 66 will lock it at 66, PCI is prelocked, then what about IDE channels? I can safely assume that its pre-locked as well, right?
 
i think this is correct.....

ide and pci are locked......agp, mem, and cpu are adjustable in its own area.....agp can be adjusted individually, cpu and ram can be adjusted together or individually...there are so many options and bios will determine right amount if you use optimal or aggressive....play with it a little and watch your ram settings auto configure......you can even set system performance to user defined and set ram and cpu differently.....or all user defined...
 
I recently burned out my Extacy Gforce4 4600ti card and is it because I didn't lock the agp bus at 66? Shop said it was a faulty heat sync or maybe the fan quit, but overclocking would defenitly kill it. I left the agp speed setting in auto, assuming it would be ok.:(
 
sorry to hear that......

i left mine on auto for about a year now and overclocking cpu fsb from standard 133fsb to 166fsb.....my card is fine.......hopefully....yesterday, for the heck of it, locked it at 66.......just for sake of it......
 
mfjonny said:
So setting AGP at 66 will lock it at 66, PCI is prelocked, then what about IDE channels? I can safely assume that its pre-locked as well, right?

IDE channels run on the PCI bus so they will run at whatever the PCI is set at.
 
I was wondering if the pci and agp bus runs at the same speed?
It might be a silly question, but I am new to this and would like to limit my mistakes. Thanks in advance.
:)
 
towcutter said:
I was wondering if the pci and agp bus runs at the same speed?
It might be a silly question, but I am new to this and would like to limit my mistakes. Thanks in advance.
:)

PCI is 33Mhz, AGP is 66Mhz

(and its not a silly question :) )
 
The AGP is set to run at 66mhz at factory settings and higher AGP bus speeds leads to corruption in video settings. You want to run you AGP at 66 because non-66mhz settings can cause serious problems.

Before locked AGP/PCI buses, a divider was used to set the AGP/PCI bus speeds. Thus a FSB of 133 would use a 1/4 divider, giving 66mhz for AGP and 33 for PCI (PCI is half of AGP), at 166, 1/5 divider was set. As long as FSB was set to either 133 or 166, there were no problems, however overclocks of anything beyond either two reference points had the potential for AGP/PCI corruptions (i.e. FSB 150 or 180).
 
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