XP 1600+ O/C questions

[Gene396]

Got a new MSI KT4 Ultra and tried out "Fussy Logic" that came with it. It got up to FSB of 168 when I halted it before something went wrong. It was running @ 1764 and temps had only risen about 2 1/2 degrees C. Now doubt -- this is a great overclock. (364 meg O/C)

My questions are: what is the divide by 4 or 5 mean and can this be used on this MB? What other ramifications are there? I know just enought to get into trouble, but enought to ask questions. My CPU is a AGOIA 02120VPBW, running 256 meg Samsun 3200 memory with ATI 8500LE video.

Any other suggestions this issue would be greatly appreciated!!

Gene

 

[drewdogg808]

the 1/4th divider basically takes the fsb and divides by 4 and sorta controls the speeds of your pci bus. so 133/4 = 33mhz. most peripherals (pci) are rated to run at 33mhz, so when you oc your fsb, you're raising the speeds of your pci devices too. say you run 145 fsb, now your pci speed is 145/4= 36mhz. the problem that occurs is when you run your fsb too high and some of your pci devices may be too high out of spec, and you run into stability problems or crashes. so you want to be careful when your hitting 38-39mhz and up on your pci devices. thats where the 1/5th divider comes in...you can run at 166fsb and your pci is back to the normal pci spec of 33mhz. 166/5= 33mhz. so having the 1/5th divider is nice in that you can hit much higher fsb than you could with just a 1/4th divider. people are actually looking forward to 1/6th dividers to run 200fsb and more. :Q this is sort of a basic explaination....i hope it helps a little.

 

[ChampionAtTufshop]

if you can select it manually, you should be at divide by 5 by now

 

[CurtCold]

I'm running the rig in my sig, 1600+, I just bumped the fsb to 166, so that's all there is to the overclock? I'm kinda wondering...

XP1600
A7v266-e
8500 ATI
512MB Kingston DDR

51C right now with thermaltak volcano 9 at 4200rpm

 

[Gene396]

drewdagg808 -- you have a way with words and your explination is very good. I surmized that FSB speeds should be a multiple of 33 as over the years FSB has risen by 33 megs each time. Note that multiply is the inverse of divide -- so we are still talking about the same thing from different directions. I have always contended that as long as you are close to a multiple of 33; it will be OK.

The only thing I could find to set the divide is in the bios and is ability to change SD RAM frequency. Available choices are 266/333/400 and auto. Mine is set to auto. So bios will automatically set the divide. Hopefully that is all that is needed on this motherboard.

I also believe that the fact that I am using 3200 DDR memory allows this large O/C.

If someone can add to this; please do!!

Gene

 

[Necrolezbeast]

I have the kt3 Ultra 2 and it auto selects the new multiplier when 166fsb is reached...likely it auto does it on your board also...

 

[CurtCold]

Update here, I have this thing running at 166fsb, and I think my benchies have gone downhill, what's up with that? The RAM timings off? I dunno, but at stock I was getting 162fps in Q3, now it's more like 131fps Demo 1....

 

[spdfreak]

I've got a KT4VL (cheap version) and it says the latest bios supports 333fsb cpu's but the dividers must be automatic, because there is no place to set them in the bios. Right now I am running a XP2000 at 144fsb very stable, but I want to put my XP1600 in and see if it will do 166. Has anyone been able to verify with Sandra or something else that the dividers do get changed automatically?

 

[MrCraphead]

How about unlocking the multiplier? I heard that you could for the 1600's? Not sure...anyone?

 

[Gene396]

After re-reading what drewdogg808 said; it seems that after setting the divider all devices (PCI) should work OK since they are working at 33 meg.

My next question is: On my motherboard I set the timing of the memory to auto which the bios will set to 333 (166x2=333 since DDR memory is double rate) did this set the memory only, or did it also set the divider for the PCI at 5?????

Another thought; since 400 (divide by 6) is available on this MB; could I up the FSB to 400? NO -- I am not going to try this as this is just way beyond any reasonable expectations (200 x 10.5 = 2100 megs)

I believe that the reason for my sucess is a advanced MB and very fast memory. This opens other ideas; unlocking CPU (very difficult, but can be done) so as to set a reasonable CPU multiplier and setting FSB at 166 or even up to 200 getting very fast speeds that the CPU could handle. This could bring new life to older Athlons and Tbirds such as the 1.0 version!!

In reading the other replys; they all think the divide is set, but are not sure. Hopefully they are correct. Again, please add as it seems others are interested in this issue!!

Gene

 

[Evadman]

I always have problems with one PCI card not wanting to run out of spec, so I always try for 166 OC then use the higher devider. Or I just unlock the chip ( which can be a pain if you have not done a bunch. I miss the Ceramic chips )

 

[BowlingNut]

i'm using a kt4 ultra and running an axp 1600 agoia y 0213 @ 166*10.5. the divider is automatically set by the board. i have three pci cards in right now and not having any problems at all, rig is completely stable and cool. (50C under 100% load for 2 1/2 hours using an swiftech mcx370-0a with the standard pabpst fan)

 

[CurtCold]

*Update on the board...A7v266-e. Overclocked the 1600+ to 1900+ speeds 1.58ghz, Pushed the fsb up to 150 133/133 Ram speeds. Running 55C with volcano 9. I'm more than happy with this chip. Wouldn't post at 166 past the bios....wahhhhh but that's how it goes...Moved my Q3 fps up to 180, from 165, have the RADEON up to 275/275!!!!


Success!!

P.S. Thanks to pillage2001 for all his help!!!

 

[MrCraphead]

Why did I think you could change the multiplier.....