Overclocking P4. How?

Starrx05

Member
Sep 29, 2005
83
0
0
I'm just curious how people overclock their P4. If they use PC3200 which is DDR400 and runs at 400Mhz I think then how do they compute or come up with their overclocked CPU speed? Most of the time, the motherboard sets the speed for CPU which is the default it's designed for. Sorry if this is a basic clueless question. And what's difference between DDR and DDR2? Thanks all....
 

Googer

Lifer
Nov 11, 2004
12,576
7
81
Welcome to the forums and a lifetime of learning about PC's!

To overclock your P4 depends on your CPU Revision and your motherboard. Older P4's you could overclock by changing the multiplier of the CPU. But AMD and Intel wanted to stop users from overclocking so they cracked down on this by locking mulitpliers that are higher than the CPU was rated for. Since they did that the only other option left was to increase the Speed of the Front Side BUS or aka FSB. Your CPU will also dictate how fast your FSB runs (400, 533, 800, or 1066MHz).

More appropriately you should ask what is the differance between SDR and DDR. Single Data Rate or SDR (aka PC66 PC75, PC100, PC133, PC142) transmits once on every rise of the clock cycle and DDR or Double Data Rate is just what the name implies it transmits on both the Rise and fall of each clock cycle or twice per clock tick. DDR2 is to DDR what SDR is to DDR. DDR2 transmits twice on the rise and twice on the fall of the clock cycle or for a total of four time per clock tick.

The trade off for this extra transmission is higher memory latency that is double that of DDR. So almost any thing gained from DDR2 is lost due to the fact that the cpu now has to wait twice as long to get the data when compaired to DDR1.

DDR2 was a rush to market design and some of the enigeers who worked on it say it's could have been better. DDR3 is suppost to address the latency issue and offer eight transmissions per clock tick.

One last note- DDR2 uses lower voltage and will not fit in a DDR1 socket. A full Four gigabytes of DDR1 uses about 40 watts of energy and DDR2 uses less than half that for the same amout of ram.