Overclocking.
- Thread starter tonester
- Start date
Slackmaster2K
Gone
This topic has been discussed a lot around here...I'll give you a brief summary:
Clock speed = bus speed x clock multiplier
PIII 450Mhz = 100Mhz x 4.5
Celeron 400Mhz = 66Mhz x 6
etc...
All Intel chips have fixed clock multipliers, which means that the only way to overclock is to adjust the bus frequency.
Consider your PIII 450Mhz...
100 x 4.5 = 450Mhz
112 x 4.5 = 500Mhz
133 x 4.5 = 600Mhz
Problems with adjusting bus speed: 1) your motherboard must support the adjustment. Many boards will *always* use the CPU defualt. 2) Your motherboard must support small enough adjustments, some only do 66/100/133 which is not handy for overclocking 3) Adjusting system bus speed will also effect the PCI and AGP busses.
In regards to #3. PCI and AGP run at some multiple of the system bus speed, and they *always* want to run at 33 and 66Mhz respectively. The selectable multipliers will depend on the chipset on your motherboard. Typical 440BX PCI multipliers are 1/4, 1/3 and 1/2 and typical 440BX AGP multipliers are 2/3 and 1/1. I mention the BX multipliers because you probably have a BX or similar motherboard. Another note: PCI and AGP busses must always run at their minimum speed or better. Let's do numbers:
66Mhz system bus * 1/2 PCI Mult = 33Mhz PCI bus (good)
66Mhz system bus * 1/3 PCI Mult = 22Mhz PCI (no good)
100Mhz system bus * 1/3 PCI Mult = 33Mhz PCI bus (good)
112Mhz system bus * 1/3 PCI Mult = 37Mhz PCI bus (ok but risky)
112Mhz system bus * 1/2 PCI Mult = 56Mhz PCI bus (no way)
100Mhz system bus * 2/3 AGP Mult = 66Mhz AGP bus (yay!)
112Mhz system bus * 2/3 AGP Mult = 75Mhz AGP bus (ok, risky)
112Mhz system bus * 1/1 AGP Mult = 112Mhz AGP bus (NO WAY)
Ok, so obviously it's best to run at a standard bus frequency of 66 or 100Mhz. Jumping up to 112Mhz on your PIII, for instance, means running PCI at 37Mhz and AGP at 75Mhz. What are the risks here? Everything on your PCI and AGP busses is now being overclocked, which can lead to failure, data corruption (remember, your HD controller is on there too), and so on. However, most devices can run a bit above their minimum rating without too much trouble. In the past I've run AGP at 83Mhz and PCI at 42Mhz without problems.
What about 133Mhz, it's standard, right? While you can select a PCI multiplier of 1/4 to run PCI at 33Mhz, there is no appropriate AGP multiplier on BX-grade chipsets so you're going to overclock your AGP card no matter what.
What about AMD? Durons and Athlons can be overclocked by adjusting the clock multiplier, which means that you don't have to worry about bus frequencies. It requires scratching the processor with a pencil a bit, but it works.
What can you expect to gain from overclocking? On the average you should expect a 10-20% improvement in clock speed. Your 450 might be able to jump to 500-550Mhz without too much trouble, but you will be running out of spec PCI and AGP. AT BEST you'll be able to jump up to the next standard bus speed. On your PIII 450 that means 4.5 * 133Mhz = 600Mhz.
More to think about: heat! You might need a better heatsink/fan, and you'll want to mount it with good thermal transfer compound. Investing in another box fan might be a good idea too.
More to think about: memory! To overclock your PIII you'll want at least PC133.
Is it worth it? On a PIII processor no, not really. I would only recommend it in certain circumstances (e.g. overclocking old Celerons was awesome). With an AMD processor I'd absolutely recommend it...you've got nothing to lose!
I suggest you see what your motherboard can handle, and then buy a Celeron II 800Mhz processor or better. 1) The Celeron II is a coppermine PIII processor with a full speed cache, your PIII 450 is not. 2) Celeron II's over 800Mhz run on a 100Mhz system bus instead of 66Mhz like older Celerons. 3) The Celeron II 850Mhz, which I recently bought and installed, can be had for $50, and Celeron II's are available up to 1Ghz at this point 4) You can continue to use your existing PC100 memory. 5) You don't have to read or understand any of the crap I mentioned in this post, or risk your components and data. The only downside is that you'll need an FCPGA to Slot1 adapter. I recommend the Asus S-370D or S-370 133. The only difference between a Celeron II 800+ and a PIII is that the celeron has half the cache, and runs at 100Mhz where the PIII EB processors run at 133Mhz.
Good Luck!
Slackmaster 2000
Clock speed = bus speed x clock multiplier
PIII 450Mhz = 100Mhz x 4.5
Celeron 400Mhz = 66Mhz x 6
etc...
All Intel chips have fixed clock multipliers, which means that the only way to overclock is to adjust the bus frequency.
Consider your PIII 450Mhz...
100 x 4.5 = 450Mhz
112 x 4.5 = 500Mhz
133 x 4.5 = 600Mhz
Problems with adjusting bus speed: 1) your motherboard must support the adjustment. Many boards will *always* use the CPU defualt. 2) Your motherboard must support small enough adjustments, some only do 66/100/133 which is not handy for overclocking 3) Adjusting system bus speed will also effect the PCI and AGP busses.
In regards to #3. PCI and AGP run at some multiple of the system bus speed, and they *always* want to run at 33 and 66Mhz respectively. The selectable multipliers will depend on the chipset on your motherboard. Typical 440BX PCI multipliers are 1/4, 1/3 and 1/2 and typical 440BX AGP multipliers are 2/3 and 1/1. I mention the BX multipliers because you probably have a BX or similar motherboard. Another note: PCI and AGP busses must always run at their minimum speed or better. Let's do numbers:
66Mhz system bus * 1/2 PCI Mult = 33Mhz PCI bus (good)
66Mhz system bus * 1/3 PCI Mult = 22Mhz PCI (no good)
100Mhz system bus * 1/3 PCI Mult = 33Mhz PCI bus (good)
112Mhz system bus * 1/3 PCI Mult = 37Mhz PCI bus (ok but risky)
112Mhz system bus * 1/2 PCI Mult = 56Mhz PCI bus (no way)
100Mhz system bus * 2/3 AGP Mult = 66Mhz AGP bus (yay!)
112Mhz system bus * 2/3 AGP Mult = 75Mhz AGP bus (ok, risky)
112Mhz system bus * 1/1 AGP Mult = 112Mhz AGP bus (NO WAY)
Ok, so obviously it's best to run at a standard bus frequency of 66 or 100Mhz. Jumping up to 112Mhz on your PIII, for instance, means running PCI at 37Mhz and AGP at 75Mhz. What are the risks here? Everything on your PCI and AGP busses is now being overclocked, which can lead to failure, data corruption (remember, your HD controller is on there too), and so on. However, most devices can run a bit above their minimum rating without too much trouble. In the past I've run AGP at 83Mhz and PCI at 42Mhz without problems.
What about 133Mhz, it's standard, right? While you can select a PCI multiplier of 1/4 to run PCI at 33Mhz, there is no appropriate AGP multiplier on BX-grade chipsets so you're going to overclock your AGP card no matter what.
What about AMD? Durons and Athlons can be overclocked by adjusting the clock multiplier, which means that you don't have to worry about bus frequencies. It requires scratching the processor with a pencil a bit, but it works.
What can you expect to gain from overclocking? On the average you should expect a 10-20% improvement in clock speed. Your 450 might be able to jump to 500-550Mhz without too much trouble, but you will be running out of spec PCI and AGP. AT BEST you'll be able to jump up to the next standard bus speed. On your PIII 450 that means 4.5 * 133Mhz = 600Mhz.
More to think about: heat! You might need a better heatsink/fan, and you'll want to mount it with good thermal transfer compound. Investing in another box fan might be a good idea too.
More to think about: memory! To overclock your PIII you'll want at least PC133.
Is it worth it? On a PIII processor no, not really. I would only recommend it in certain circumstances (e.g. overclocking old Celerons was awesome). With an AMD processor I'd absolutely recommend it...you've got nothing to lose!
I suggest you see what your motherboard can handle, and then buy a Celeron II 800Mhz processor or better. 1) The Celeron II is a coppermine PIII processor with a full speed cache, your PIII 450 is not. 2) Celeron II's over 800Mhz run on a 100Mhz system bus instead of 66Mhz like older Celerons. 3) The Celeron II 850Mhz, which I recently bought and installed, can be had for $50, and Celeron II's are available up to 1Ghz at this point 4) You can continue to use your existing PC100 memory. 5) You don't have to read or understand any of the crap I mentioned in this post, or risk your components and data. The only downside is that you'll need an FCPGA to Slot1 adapter. I recommend the Asus S-370D or S-370 133. The only difference between a Celeron II 800+ and a PIII is that the celeron has half the cache, and runs at 100Mhz where the PIII EB processors run at 133Mhz.
Good Luck!
Slackmaster 2000
ola
Newbie
Overclocking is a typica "because you can" thing. The effort, time to get it to work (if it ever will) and money for exrta fans etc. will never be worth the difference in price compared to a faster processor at factory speed.
Unless you peliter/water cool a really fast processor and get it to run at speeds you cannot get in the store...just because it can be done.
/ola
Unless you peliter/water cool a really fast processor and get it to run at speeds you cannot get in the store...just because it can be done.
/ola
thanks
well guys, thanks for your help. it seems easier , cheaper and safer in the long run to just upgrade my chipset.
Assuming my Tabor II motherboard can handle it.........
Basically i just want a faster processor to handle the software synths that are out there. I find that I get a CPU warning and audio engine shut off in a lot of the patches in Tassman. Also, I think my SONAR XL would run a lot smoother, without as many dropouts.
Tony
well guys, thanks for your help. it seems easier , cheaper and safer in the long run to just upgrade my chipset.
Assuming my Tabor II motherboard can handle it.........
Basically i just want a faster processor to handle the software synths that are out there. I find that I get a CPU warning and audio engine shut off in a lot of the patches in Tassman. Also, I think my SONAR XL would run a lot smoother, without as many dropouts.
Tony
tubedude
New member
With something like a 1.4 Athlon and an Iwill kk266, all you have to do is connect some "jumpers" on the CPU with a conductor pencil (whatever its called) and then you can set the bus speed up in the bios setup. Easy as pie, for the most part. That boards bus speed I think can be clocked up to 151mhz stable. Thats pretty good, and helps eliminate that bottleneck at the CPU.
There is a site that illustrates the whole process, but I cant rem the name, I'll post it when I find it.
There is a site that illustrates the whole process, but I cant rem the name, I'll post it when I find it.
tubedude
New member
As soon as I post I rem... www.anandtech.com just search around for the iwill kk266 review, and they'll eventually tell you how its done, with pictures. 
Queue
Active member
I have a semi out-dated system, and overclocking is keeping it alive!
AMD K6 III+ 450 O'Cd @550
FIC 503 VA Mobo
The cool thing about the K6III+ is it can be controlled with software!!! I can just run a little proggie, and bump my multiplier. That CPU is designated as a "mobile processor" destined for laptops, but the nice folks at FIC upped the BIOS on my MOBO to accept these CPUs. I'm guessing it breathed a few years of life into my current machine.
Queue
AMD K6 III+ 450 O'Cd @550
FIC 503 VA Mobo
The cool thing about the K6III+ is it can be controlled with software!!! I can just run a little proggie, and bump my multiplier. That CPU is designated as a "mobile processor" destined for laptops, but the nice folks at FIC upped the BIOS on my MOBO to accept these CPUs. I'm guessing it breathed a few years of life into my current machine.
Queue
mikahawkins1
New member
Make sure you have a good cooling system before you start running that horse at high speed.
mikahawkins1
New member
Hello there tony,
I see that you need help with overclocking, I am going to give you these softwares for help.
Have a great day!
TalismanRich
Well-known member
Wait a minute, Dale.
I think I've got an old AMDK6-450 under the pool table. I wonder if I could overclock it enough to keep up with a new Ryzen 7? I think I had it bumped up to a full 512K memory, which is almost as much as Bill Gates said is the most we'll ever need.
I think I've got an old AMDK6-450 under the pool table. I wonder if I could overclock it enough to keep up with a new Ryzen 7? I think I had it bumped up to a full 512K memory, which is almost as much as Bill Gates said is the most we'll ever need.
DaleVO
Poor Farm Productions
Talis....,
You and I sound a lot alike. I bet I still have my old Radio Shack TRS 8088, on the shelf down at the shop. I recall spending close to $1000 for it, the RGB "color" monitor, and a dot-matrix tractor-feed printer. Oh my- old days of DOS shell and commands. Good experience, but I sure wouldn't want to go back.
Dale
You and I sound a lot alike. I bet I still have my old Radio Shack TRS 8088, on the shelf down at the shop. I recall spending close to $1000 for it, the RGB "color" monitor, and a dot-matrix tractor-feed printer. Oh my- old days of DOS shell and commands. Good experience, but I sure wouldn't want to go back.
Dale