overclocking

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Meithan said:
Memory is one of many factors that can limit overclocking potential. It doesn't always restrict it. The thing with DDR is that it has low clock frequencies, and that's why it can represent the first limitation.

It's quite the same thing with Intel, except Intel doesn't use HyperTransport, just a good ol' quad-pumped front side bus (FSB). Quad-pumped just means the advertised FSB frequency is four times the real FSB speed (for instance, 800Mhz FSB is 4x200Mhz). What's important is the real speed of the bus (200Mhz being a sound value for the CPUs in that range), so it doesn't matter if it's a dual-data rate, multiplied AMD HyperTransport bus or a quad-pumped Intel front side bus.

Just as an example, tell me your exact CPU speed (stock and OCed), memory speed and FSB, so we can figure it all out.

CPU stock is 2.4GHz, and I'm running DDR PC3200. OC'd speed on my proc is 3.2GHz.
 
You didn't specify, but I'm guessing you have a Northwood or Prescott. Either way, your FSB must be running at 800Mhz (4x200Mhz). CPU stock clock is 12x200Mhz = 2.4Ghz. A 3.2Ghz overclock was likely achieved by upping the FSB from 200Mhz to 266Mhz. Using PC3200 (DDR-400) RAM, with a 1:1 memory settings the RAM would be overclocked to 266Mhz (~PC4300). I doubt ValueRAM can go that far, so your motherboard is probably using a memory divider.

I checked your board's manual and it's capable of the following FSB:RAM settings: 3:2, 5:4, 1:1 and 4:5. The first two are dividers (RAM slower than FSB), 1:1 runs RAM and FSB in synch, and the 4:5 setting is a multiplier (RAM faster than FSB). They don't appear as such in your BIOS, though. They show up as DRAM Frequency settings DDR266, DDR333 and DDR400. Depending on the FSB, they correspond to the settings I mentioned above.

So with an OCed FSB at 266Mhz, the RAM setting must be either 3:2 or 5:4 (DDR266 or DDR333 in your BIOS). With 3:2, the RAM is dowclocked to 266Mhz * 2/3 = ~177Mhz; with 5:4, it's overclocked to 266Mhz * 4/5 = ~213Mhz. Naturally, the higher the better, but since it's ValueRAM, there's no guarantee the 13Mhz overclock is possible.

Check your BIOS and verify your DRAM Frequency setting, please, so that we can see if I'm correct. In the unlikely case it's set at DDR400, you're getting a 33% overclock on ValueRAM, which would be impressive.
 
Here's what's listed under Frequency/Voltage control in my BIOS:

CPU Bus Clock: 178MHz
DDR Clock: 445MHz
AGP/PCI Clock: 89.00/44.5MHz
CPU VCore: 1.525V
DDR Voltage: 2.65V
AGP Voltage: 1.5V

Does that help?
 
Uhm. I was assuming you were running FSB 800 originally, but it seems not. The next possibility (considering your motherboard) is FSB 533, which is 4x133Mhz. This produces 2.4Ghz with a 18x CPU multiplier (I believe this is the maximum supported by your motherboard).

Clearly, you overclocked your FSB 45Mhz, and the memory reflects it by running at 445Mhz DDR (223Mhz real). The FSB:RAM ratio hasn't changed: it's on a 4:5 multiplier. With this new FSB you achieve 18 x 178Mhz = 3.2Ghz.

As you can see, it all works out now. It's nice to see the value RAM overclocked 23Mhz (or 45Mhz DDR). And overall you got a very good overclock. Congratulations.
 
Meithan said:
Uhm. I was assuming you were running FSB 800 originally, but it seems not. The next possibility (considering your motherboard) is FSB 533, which is 4x133Mhz. This produces 2.4Ghz with a 18x CPU multiplier (I believe this is the maximum supported by your motherboard).

Clearly, you overclocked your FSB 45Mhz, and the memory reflects it by running at 445Mhz DDR (223Mhz real). The FSB:RAM ratio hasn't changed: it's on a 4:5 multiplier. With this new FSB you achieve 18 x 178Mhz = 3.2Ghz.

As you can see, it all works out now. It's nice to see the value RAM overclocked 23Mhz (or 45Mhz DDR). And overall you got a very good overclock. Congratulations.

Sorry, I got a brain fart yesterday. LOL. I didn't realize until late last night that my processor's FSB was 533, not 800. I've been considering trying to push it a bit more, but I don't think I will now. When I'm not doing anything, F@H processes a frame in 13 seconds. I'm quite happy with that. LOL.
 
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