Overclocking Your P4 800FSB - Getting Into That BIOS
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Speaking of that process, here is where it all happens. Yes, I know, there are now many Windows based overclocking tools that come with many motherboards, but I'm not really interested in hosing my O/S while I'm still in it. Call me old fashioned (well, not that old fashioned, I love BIOS tweaking way more than I ever liked playing with jumpers), but it's a pretty reliable way of getting the job done.
Different motherboards have different options, different places for those options, and even different names. I'll try and make this as general as possible. Still, the best way to figure out how this equates to your specific situation of course, is to read your manual! I'm not kidding, this is something that I wish wasn't overlooked so often.
Usually the fun stuff is found under "frequency/voltage options", "softmenu", or "AI". This is where you'll find your options for changing the Front Side Bus, CPU voltage, RAM voltage, PCI/AGP bus frequency, and sometimes the frequency for RAM as well as the timings for it. EPoX, Abit and ASUS tend to be very good in laying this all out in one place, however more pedestrian boards like my Soltek have these options all over the BIOS. You'll just have to do some hunting. If you have a genuine Intel motherboard though, don't bother. They do not condone overclocking of their chips, for the obvious reasons.
The first thing to do, when you get in here, is remember all the settings that worked. If you are going to push the envelope, chances are you'll eventually find yourself putting in a setting that will cause your system to not boot. Then, after looking in your manual to find it, you'll get acquainted with the CMOS reset jumper. Then when you come into the BIOS, all the settings will be at crappy default ones, that might not even have your CPU at the right speed. Also, the "load defaults" are usually pretty crappy. I'd personally rather just set things myself.
Here is a common first page for many boards. Nothing too exciting here. However, the good parts are just around the corner. Peeking into the "standard bios options" on this Soltek, or under many other names on other boards, you can find some of the parts that are useful. The first one I usually check into is "hardware health monitoring". Now, I'll be the first to say that NONE of these readings are actually correct, and the temp ones might not even be in the ballpark. However, it's better than nothing, and you can usually gather an estimate, once you know more or less how it's calibrated. In the temp, as long as it's not soaring, or constantly changing, you are going to be happy. Having a rising temperature, when the CPU is under no load, is an indication of your heatsink being off kilter. With a P4, you really don't have to worry so much about what temp it's at. Intel is really good about the inclusion of "suicide watch" circuitry. If the processor gets too hot, it starts operating at slower and slower speeds until the temperature is more under control. It also has an auto shutdown if it reaches a certain temperature. This of course is read from a much more accurate internal diode, who's signal does not get sent out side the chip. Looking at the voltages, you basically want to make sure nothing is completely out of whack. The Vcore, Vdimm, or other VAGP that you've set, while they may not be exact to what you'd like them to be, should at least be different from the settings you changed them from.
Some BIOS allow you to mess with the memory timings as well, all in that one simple area. Unfortunately for me, that's not the case here. Heading back out, you might have to make your way back into the "advanced chipset" menu. From here, you have access to the memory/FSB ratio, as well as the timings for the RAM. By checking out the article on
Memory Bandwidth and Timings, you can find out what all these mean. Generally, you are going to want to use the tightest timings you can get away with. There is only one way to find this out, and that's through testing. Using the memory divider, you can keep your memory somewhat within spec. Since I have cheap PC3200, almost any overclock is going to require switching to the 5:4 divider, and anything much over 250MHz FSB causes me to kick in the 3:2 divider.
Next: Testing >>
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