PCI-E overclocking?

[Just4Ever]

Hi, I was just wondering if people overclock their PCI-E port as when the overclock their GPU. Right now I have the ASRock 775Dual-VSTA motherboard with an eVGA 7900GT. I know my board is cheap but I will be getting a new one in a month or two. Regardless, is it safe to overclock this setting in bios?

If I do overclock it, how does it affect the speeds of the GPU?

Finally, is the performance gains worth it if this is indeed risky?

Thanks guys.

P.S. The reason I'm asking is because my bios has a setting where I can overclock the FSB along with the PCI-E in sync.

 

[Lord Evermore]

You'll get no performance gain in all likelihood. PCIe is already beyond the bandwidth video cards need (although the PT880-Pro is I believe only x4 PCIe, which is equivalent to AGP4X) . Most video cards can't even handle bus overclocking all that well, which is why mainboards introduced separately-controlled speeds for the PCI/AGP/PCIe clocks, whereas they used to be just a multiplier of the main FSB. I don't know how they handle PCIe overclocking, people rarely even bother, they just lock them at defaults.

You are unlikely to actually hurt anything if you try it. Voltage increases are what kill hardware, or allowing them to run at high speeds and putting out lots of heat with inadequate cooling.

The clock speed of the GPU and memory are unlikely to change, I don't think they're based on the bus speed, they just have their own clock generator.

 

[Noubourne]

Some people seem to get more overclock out of their GPU if they kick up the PCIe bus a bit. Of course, these people already have custom cooling and often volt mods installed on their GPU already, so we're not talking about your generic everyday users who seem to benefit from this.

SATA often runs off the PCIe bus though, and you can corrupt your data if you do it with SATA running off the PCIe bus. I've seen people switch back to IDE so they can kick their PCIe bus up to 110+ and get another 50 3dMarks or something. The general rule is it's not worth it unless you're dying to break the latest 3dMark record.

Some people say it's safe to do up to 105 even with SATA running off it, but I'm not a big fan of reinstalling my OS, so I haven't done it.

 

[cmdrdredd]

Originally posted by: Noubourne
Some people seem to get more overclock out of their GPU if they kick up the PCIe bus a bit. Of course, these people already have custom cooling and often volt mods installed on their GPU already, so we're not talking about your generic everyday users who seem to benefit from this.

SATA often runs off the PCIe bus though, and you can corrupt your data if you do it with SATA running off the PCIe bus. I've seen people switch back to IDE so they can kick their PCIe bus up to 110+ and get another 50 3dMarks or something. The general rule is it's not worth it unless you're dying to break the latest 3dMark record.

Some people say it's safe to do up to 105 even with SATA running off it, but I'm not a big fan of reinstalling my OS, so I haven't done it.

Never thought of that. Good point though, something I didn't know.

 

[Just4Ever]

I'm not running SATA so I don't have to worry. But I am using the ASRock 775Dual-VSTA which only has PCIe x 4. So would boosting it help if my PCI-E slot only has 4 lanes?

 

[Vinnybcfc]

It may help have a go and see how much performance increases, raise 5mhz every time then run a benchmark until you hit the limit then clock it back down a mhz each time until you find a good spot