Whats the deal with PCI CLOCK 33.33Mhz?? Tags: CPUs Overclocking PCI Last response: March 18, 2006 3:16 AM in Overclocking Share style69 March 18, 2006 2:51:03 AM Hello. SO i have a moderate overclock of 2.25 Ghz on my 3200 venice. vcore 1.35 should i set the PCI synchronization of something to 33.33? or leave it as auto? Whats the difference? More about : whats deal pci clock 33mhz TabrisDarkPeace March 18, 2006 3:16:00 AM If your PCI clock gets over 37.5 MHz expect some issues with some cards plugged into it. The PCI bus speed can be a ratio, or it can be locked as 33.33 MHz. It is generally better to lock it at 33.33 MHz as if it raises to much you'll have issues. The SATA bus, AGP / PCIe x16, and HTT buses can all also be affected if they are out of spec by more than 12.5%, for SATA even less (+/-3% is best). However some SATA controllers are not affected by bus speed changes, others are, etc, etc Also if you overclock the FSB to the 'next divider' the PCI bus will go down to 33.33 MHz again. eg: :arrow: 100 FSB / 3 = 33.33 MHz :arrow: 115 FSB / 3 = 38.33 MHz (too high) :arrow: 133 FSB / 4 = 33.33 MHz again (so stable, assuming the CPU can handle a +33% overclock. The same rule tends to apply when going from 133 to 166, 166 to 200, etc, the divider raises by one every 33.33 MHz, to keep PCI bus stable. 133 to 166 is only a +25% CPU overclock 166 to 200 is only a +20% CPU overclock ....and so on. Some chipsets / mainboards may not be affected by it, and just lock the PCI bus to 33.33 MHz. It dates back to the origin of the PCI bus, back in the Pentium 60 and 66, and keeps everything in sync nicely. Having things in sync nicely may let you overclock more than running the PCI bus async, or it may not..... there are many variables to consider. Can't find your answer ? Ask ! Publish Related resources Whats faster... SLi: (TWO) BFG 8800 Ultra Over Clocks (PCI-e x16) or SLi: (TWO) THE FASTEST PCI-e x16 2.0 (@ x8 bandwidth) Forum Solvedwhats wrong with my microphone and how am i supposed to deal with it? Forum What is the Max FSB Setting to Secure PCI Clock Forum SolvedWhats the deal with this website Forum SolvedFirst time, whats a good clock to have? Forum SolvedWhats the deal with my resolution? Forum SolvedWhat's the deal with SLI? Forum SolvedAbout to buy a PC, want opinion if its a good deal and will work for what I'm looking for Forum SolvedWhats best for sli PCI-E x16 both or x16/x8 Forum SolvedWhat's the difference between Overclocking and Boost Clock? Forum Solvedso what's the deal with optical drives? Forum SolvedWhat is a safe over clock for my alienware m14x r1, which has a gt555m video card? Forum Whats the big deal? Forum SolvedWhat's the point of a "GHz edition" card when i can just over clock myself? Forum SolvedWhat is Memory Timing? And what difference does Memory Clock make? Forum SolvedWhats the big deal with SSDs? Forum SolvedI purchased a used rig for $400, please tell me what i need to upgrade and if it was a good deal Forum Solvedwhat the difference between PCI-E x16, x1 and normal PCI Forum I have a Time capsule for my wi-fi and am having trouble getting more than one person getting wi-fi. Whats the deal?? I don't Forum SolvedWhat is the deal with AMD's pricings lately? Forum More resources Read discussions in other Overclocking categories CPUs Motherboards Memory Chipsets Heatsinks Water Cooling Intel AMD !