Dare I set CPU Frequency to 166MHz in BIOS?

[dderolph]

I've never delved into overclocking. I have an ECS K7S5A PRO motherboard. In the BIOS Setup screen, CPU Frequency is set to 133MHz; same for DRAM Frequency. At this setting, my CPU runs at the rated speed.

When I first installed my motherboard, the fastest setting shown in CPU BIOS Setup for CPU Frequency was 133MHz. This makes sense, since this motherboard is supposed to support up to 266MHz FSB processors. Do I understand this right?

Subsequent to installing my motherboard, I've discovered that my BIOS Setup screen shows 166MHz as an option for CPU Frequency. I believe this change occurred around the time that I installed SP2 for Win XP; I don't know if there's a connection between these events, but that's my recollection.

I'm not sure what to think about this 166MHz option. Surely, I my Athlon XP 2200 won't run at that setting, right? Should I take this to mean I could install a processor that runs at 333 FSB?

 

[BlueWeasel]

Yes, if the K7S5A Pro board supports a FSB of 166, then it should be able to run the newer 333Mhz Barton chips (you might need a BIOS update though).

Is the XP 2200+ a Palomino or Thoroughbred core? The Palominos don't really have much overclocking headroom at all, but it might be possible to hit 166 FSB with a Tbred chip. However, if you're using PC2100 RAM, then the RAM may not be able to hit 166 FSB even if the processor can.

I don't think it would hurt to try, but make sure going up to the higher FSB doesn't overclock the PCI and AGP (ie, you've got a divider to keep the PCI and AGP buses at 33 Mhz and 67 Mhz, respectively). My brother has a non-Pro K7S5A (no 166 FSB option in the BIOS), and I corrupted his Windows installation just by overclocking to 142 FSB.

I'd just try it and see, but check on the corruption issue beforehand. You'll probably need to bump the core voltage a 0.1v or so, and your RAM may need a voltage bump if it's PC2100. Make sure you know how to reset BIOS settings if the system doesn't boot after overclocking.

Have I overwhelmed you enough?

 

[dderolph]

I'm not sure whether my processor has a Palomino or Thoroughbred core. Anyway, I tried changing the setting to 166MHz and my computer would not boot up. I had to use a jumper on the motherboard to clear CMOS settings, then go back in and re-set my settings. Scarry. Enough experimentation. I'll just keep in mind that I should be able to use a processor with a 333MHz FSB. However, I presume I would need to get 166MHz memory to go with a 333MHz FSB processor for optimum compatibility between them, right?. I'll keep these things to keep in mind for the future, but I'd probably replace the motherboard, too, when the time comes that I'm looking at another processor.

 

[BlueWeasel]

Yeah, if you've got PC2100 RAM, then you will likely need to upgrade the RAM to PC2700 or PC3200 if you get a 333 Mhz processor.

Also, you can use a program like CPU-Z that will tell you the core of your processor, as well as provide information on the speed of your RAM.

 

[dderolph]

OK, thanks for that tip.

 

[BigBadBiologist]

The ECS K7S5A PRO doesn't have a memory divider to let you use slower RAM than the FSB?

 

[dderolph]

Not sure what you mean by "memory divider"; as it see it, it will let me set "CPU Frequency" to 166MHz and set "DRAM Frequency" to 133MHz. So, apparently, I could install a 333MHz (2x166) FSB processor with my PC2100 RAM.

 

[BlueWeasel]

Originally posted by: dderolph
Not sure what you mean by "memory divider"; as it see it, it will let me set "CPU Frequency" to 166MHz and set "DRAM Frequency" to 133MHz. So, apparently, I could install a 333MHz (2x166) FSB processor with my PC2100 RAM.

Yep, that's the memory divider which lets you run the RAM and CPU at different speeds. The XP suffer a performance hit when the RAM and CPU aren't running at a 1:1 ratio. But that would let you see if your 2200+ can run at 166 FSB while leaving the RAM at 133.

 

[dderolph]

From my previous post: "Anyway, I tried changing the setting to 166MHz and my computer would not boot up. I had to use a jumper on the motherboard to clear CMOS settings, then go back in and re-set my settings."

 

[BigBadBiologist]

It could have been your RAM that prevented you from working at 166FSB. If you set your memory divider to a lower speed RAM, you may be able to overclock the CPU more. (if you have your memory set to 100MHz, when your memory will actually be at 133 when you set your FSB at 166 --- see it's really easy math )