OC question... - Tech Support Forums

Kara C · November 11th, 2003, 06:42 AM

I was reading that it's better to have the system memory running at the same speed as your cpu fsb for optimal results is this correct? Right now I have 1gig of ddr 2100 running at 266 if I recall correctly. Now if I wanted to tweek my cpu Amd XP 2100/266fsb I am guessing I would have to do that trick where you use pencil lead to enable oc on the cpu correct? I have a decent board Abit AT7-MAX2 so its just a matter of unlocking the cpu..its not a barton chip but I am still hoping that this is possible despite that. Anyway any suggestions tips etc would be great, and in the meantime I will read up a little more on the subject so I can avoid melting the computer!

DallasDon · November 11th, 2003, 06:59 AM

Is your processor now running at 1733 mhz? if so, that is the stock speed, 266 MHZ FSB. The stock multiplier is 13X.

If you have ddr 2100 running in sync, 1/1 ratio with the processor, it is already overclocked. Stock FSB for that ram is 200 MHZ.

Read up in your mobo manual to see if you can change the multiplier in the BIOS setup. You might try upping the multiplier 1/2 half step at a time, and run a burn in test after each change.

To reach 2GHZ, 2400+ speeds, you would need 266 FSB x 15, with a Voltage of 1.6 to 1.65

Overclocking may produce around a 20% performance increase, or a disaster. Be sure to consider all the advantages/disadvantages before undertaking it, and be prepared to suffer the consequences.

muno · November 11th, 2003, 07:04 AM

You mixed up memories there

PC1600 runs at 200mhz ddr, PC2100 runs at 266mhz ddr.

So the memory is not overclocked.
-M

//edit:
Oh, there is no pencil trick on athlon xp processors. You would need to fill the gaps and do some stuff and everything.

Easiest way would be to just overclock the fsb, not the multiplier.

John Prophet · November 11th, 2003, 07:09 AM

uhh, Dallas Don....I think PC2100 runs at 133X2 which = 266.

PC1600 was the 100mhz type

http://computermemoryupgrade.mysuper...rade_faq.shtml

Quote---->

PC1600 memory runs at a FSB speed of 200MHz
PC2100 memory runs at a FSB speed of 266MHz
PC2700 memory runs at a FSB speed of 333MHz
PC3200 memory runs at a FSB speed of 400MHz

Kara C · November 11th, 2003, 07:10 AM

For some reason I thought these could not be OC unless they were unlocked? But hey would not be the first nor last time I have been wrong.

DallasDon · November 11th, 2003, 07:12 AM

uhh, Dallas Don....I think PC2100 runs at 133X2 which = 266.

MY bad, really tired from a long day. Bookmarked your link, JP.

Thanks for the wake up call.

John Prophet · November 11th, 2003, 07:21 AM

ya, well in a certain sense it is obvious because the standard ddr now is pc2100 and obviously if wouldnt be standard if it only ran at 100mhz, cuz that would be a serious bottleneck since 133x2=266 is the "standard" cpu fsb nowadays.

But I know how it is, there are just wayyy toooo many numbers to be memorizing on these dang comps. If I try to quote the speeds for the pc2700 or 3200 I usually get em wrong, lol.

John Prophet · November 11th, 2003, 07:29 AM

Kara..the "unlocked" part is speaking about the multiplier...it has nothing to do with the fsb.

For instance on an old Pentium 2 400 it would be a 100fsb x a "4" mulitplier = 400mhz.

So if you bumped up the fsb to 101 and left the multiplier at "4" you would have an overclock to 404mhz. If you go to 105 you are running at 420....but you are running the pci bus at about 35mhz.

There is a limit to how far the fsb can be bumped because it speeds up other stuff like the ram etc and eventually something locks up....so if you can unlock the multiplier you could bump the multiplier to 4.5 and drop the fsb back to 95 you would have a cpu running at 427.5 but the pci bus and memory etc would then be slightly "underclocked"..but at least the pci cards wont be locking up etc. So if you get the multiplier unlocked you have WAY more flexability.

The trick is that when you bump up the fsb you are also bumping up other stuff like the ram, pci bus clock and the agp clock...so in effect you are overclocking your pci cards and video card also.

That is where "locks" and "dividers" come into play. The nice motherboards have "locks" that keep the pci and/or agp at the same speed even if you bump up the fsb. And dividers help keep the pci and agp within workable speeds also.

When you try to go to a certain fsb and it locks up, then you have to be a detective and figure out whether its the ram, or a pci card, or the vid card locking up, or maybe even the cpu, or a heat problem.

JP

Kara C · November 11th, 2003, 08:16 AM

Well as I figure it its a old cheap chip..so before I go and upgrade to a new barton, figured might as well make the most of what I have now?
Anyway tried OC and course it locked up had to discharge the cmos and reset bios, no biggie ..long as I can keep getting it to boot after my failed attempts. Ruled out overheating temps are pretty constant 43c not great but I can live with that number.
So just keeping playing with it and perhaps I may get it right
eventually. Thanks for the info and help everyone!