Any benefits in Overclocking your PCI-X bus?

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teletran8

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I have an AM3 system and in the bios I can adjust PCI-X frequency from 75--250MHz.

By default settings it runs @ 100MHZ. I ran Vantage just now @ 110MHz and no errors or problems. Is this safe for my graphics card and mobo, should I be playing around with this setting?

Pro's Cons etc from anyone. This never seems to be discussed in tech sites or on these forums since I have been a member. What do you all say?
 
Common wisdom is that other components such as the SATA controllers run on that bus, and overclocking it can cause data corruption over time.

I'm assuming you mean PCI-E, I don't know of any PCI-X graphics cards.
 
Theres very little if any actualy adventage to OC'ing your PCI Express lanes and it can seriously damage your motherboard even with a very small overclock. so no I wouldn't recomend it unless you are doing extreme bech marking and don't mind risking your hardware.
 
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pci-slots.jpg

http://en.wikipedia.org/wiki/PCI-X#Confusion_with_PCI-Express

As everyone else has noted, the negatives of overclocking your expansion slots (whether they are PCI, PCI-X, or PCI-E) far outweigh the benefits.
 
:eek: OK I guess I better not be to daring and play around with the speeds, plus little benefit but that 9600gt article claims 10 percent more performance from the card...hmmm ha lol

bholstege said:
Common wisdom is that other components such as the SATA controllers run on that bus, and overclocking it can cause data corruption over time.

I'm assuming you mean PCI-E, I don't know of any PCI-X graphics cards.
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Interesting....
 
Motherboard manufactures started adding the ability to adjust PCI frequencies way back when overclocking in general became popular. People would overclock there systems and the PCI/AGP busses would be changed. Sometimes resulting in them frying there graphics cards etc... Adding the ability to keep your other items at there respective speeds helped. BIOS's have come a long way since those days, just not long enough.
 
You should lock your PCIe clock at 101 to 104MHz max.Higher clock gives you no real benefit and can also damage your HDD,LAN etc. as they all use the PCIe bus.
 
Can anyone provide evidence of permanent damage being done by raising the bus clock?

I've never seen any evidence of this assertion that's thrown around here and other forums.
 
linuxdude9 said:
Can anyone provide evidence of permanent damage being done by raising the bus clock?

I've never seen any evidence of this assertion that's thrown around here and other forums.
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you can always try it yourself and provide evidence to prove everyone else wrong about pci-e overclocking lol :p:cool::D No, really, overclock your pci-e bus to 150mhz and run it like that for a month, or a week at least... then you'll have your evidence - either way :D
 
woodscomp said:
Motherboard manufactures started adding the ability to adjust PCI frequencies way back when overclocking in general became popular. People would overclock there systems and the PCI/AGP busses would be changed. Sometimes resulting in them frying there graphics cards etc... Adding the ability to keep your other items at there respective speeds helped. BIOS's have come a long way since those days, just not long enough.
Click to expand...
I killed a PCI modem that way... I was trying to overclock my K6-2 350 to 515MHz (115x4.5) on a Asus P5A, and I noticed that my (blazing fast 44Kbps) dialup connection died on me, the phone line was working, and then I noticed that my modem had completely disappeared!

I guess some devices couldn't take a 38.3MHz PCI bus speed. Though, my SiS 6326 PCI VGA card could handle all the way up to 43MHz PCI clock...
 
I have been overclocking computers for a few years and am no means a expert.I have read in many places that adjusting the PCI-E clocks can help in stability in high overclocks.In all my research I have not found any other gains in doing so.I have always kept mine at 100mhz.
 
I'd like to see someone with an EE and/or CpE background tell me it'll cause permanent damage -- it doesn't make sense to me. You're not raising the voltage -- if the devices can't operate at the clock speed, would figure they'd just fail to operate until you lower the clock speed.

Correlation is not causation -- just because a device fails while your bus is overclocked does not mean overclocking the bus caused the failure.
 
Everything I've read/heard says its not worth the gains. More than likely you'll just introduce system instability. If you want to overclock a system, stick to the CPU first (biggest gains), then the GPU/VRAM (modest gains), then perhaps system memory (smaller gains depending on architecture - Sandy Bridge's memory controller for example holds you back from getting all that much extra performance from overclocked RAM, where as an x58 setup would net a more significant gain.)

Takeaway: Overclocking the PCI bus for performance gains is like running against the wind while wearing a parachute... you might take off a little bit, but you won't get very far, you'll sweat a lot and fall on your ass continuously.
 
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