Rookie overclocker needs advice....

[Jedibus]

I'm looking for a highly overclockable motherboard (with onboard sound) on a budget. Never did this before so the simpler the better.

I'm expecting to pick up an Athlon XP1600 because I've been reading that they are very overclockable. I will also be overclocking a GeForce4 TI4200 128 meg video card when their price drops a little more. I already ordered the Antec SX1080B which will be stocked with fans and comes with the True Power 430 watt power supply.

I did a search for motherboards relating to the XP1600 and saw some posts regarding a Shuttle mobo. I have also read that Abit boards are the best for overclocking which is my main goal.

What do you guys think?
Thanks in advance for any suggestions, flames, lies, etc...

 

[CedarTeeth135]

If you want to overclock, I recommend any Intel PIVas. Most people are successfull with the 1.6a and are able to reach 2.4+ with air coooling.

I would just say that if you are going to overclock, get a Pentium, as they are much cooler, and have less risk of frying.

 

[Boonesmi]

if you want to overclock an cp 1600+ i would get the epox 8k3a+

that board was designed with overclocking in mind
plus i love the 1/5th pci divider!!! great for keeping the rest of the system in spec when running the fsb at 166mhz

my current system is an epox 8k3a+ with an unlocked xp1500+ running a multiplier of 10x on a 170mhz bus (giving a speed of 1700mhz or a PR rating of xp 2050+)

not to mention it ohh so stable the only times it needs to be rebooted is if i install something that requires it.

 

[Jedibus]

CedarTeeth135, I've been focusing on AMD chips because of the price/value and I'm also a little familiar because I built my last pc which is a 1 gig T-Bird.

Boonesmi, I'll check prices on that Epox board. I don't even know what a pci divider is! Sounds like you did a nice OC'ing job there. Care to write a How To?

 

[Boonesmi]

hehe there are people here 100x more qualified then me to write a "how to" on overclocking

but as to your question about the pci divider...
almost everything in your system, everything from all your addin cards, onboard stuff like sound and usb, also your harddrives.. they all run on your pci or agp bus (just the vid card is on the agp bus)

agp is designed to run at 66mhz and pci at 33mhz... if these get to far out of spec then stuff stops working, one of the first things to usually go is the usb... you also run the risk of data coruption on the harddrive

agp and pci run as a fraction of the fsb... for example a motherboard that supports both 100mhz and 133mhz fsb (meaning it officially supports it, not that it can just overclock to higher fsb) but when the fsb is set at 100mhz then the pci divider is set at 1/3rd and the agp at 2/3rd (thus giving you a pci and agp bus speeds of 33 and 66mhz)... and if the fsb is set over 133mhz then the new dividers kick in at 1/4th and 1/2 (again giving you a pci/agp speeds of 33 and 66mhz)

with some of kt333 based boards, epox being one of them, if you get the fsb over 166mhz then a 1/5th and 2/5th dividers kick in again keeping the pci and agp in spec at 33/66mhz.... if the board doesnt have the 1/5th divider then at 166mhz you will have a pci of 42mhz and agp at 83mhz... with a pci bus this high you run a very high chance of having problems with any number of things

 

[Jedibus]

Ok, so having the pci divider is a good thing because it keeps the pci and agp at their default speeds if I decide to overclock the FSB. Now I would overclock the FSB to overclock the processor, right?

 

[Boonesmi]

increasing the fsb will overclock the cpu

basically your cpu speed is determined by 2 things
first is the fsb
second is the multiplier

for example all athlonxp cpus have the same default fsb(133mhz) but the difference is the multiplier
a cpu that runs 1.3ghz has a fsb of 133 and a multiplier of 10x (simple math gives you 10x133=1330mhz or 1.3ghz)

multipliers are adjustable in .5 increments
xp1500+ is 1.3ghz or 10x133 (the 10x is the default multiplier of xp1500+... just means it runs the cpu 10 times the speed of the fsb)
xp1600+ is 1.4ghz or 10.5x133
xp1700+ is 1.46ghz or 11x133
etc etc (just in case your wondering the formula for finding the athlonxp performance rating is (PR/1.5) + 333 = cpu speed... (1500/1.5 + 333 = 1330mhz, 1.3ghz

increasing either the fsb or the multiplier will overclock your cpu

most cpus come from the factory with the multiplier locked.. with a locked multiplier it means you cant change it, so if you want to overclock you have to increase the fsb

or you can unlock the cpu multiplier... it takes a little time/effort and a steady hand + it voids any warranty so its not for everyone but with an unlocked cpu you can turn it into anything you want, you can set the fsb and the multiplier at any setting you want

 

[Jedibus]

Thanks for the awesome explanation! I'll have to read it a few times before it fully sinks in Do you know the difference between the Epox 8k3a and 8k3a+? Newegg has the 8k3a refurbed (and oem ) for $55.

 

[Boonesmi]

im pretty sure the only difference is the + has onboard raid

different revisions of the 8k3a+ have different onboard audio chip (the new revisions have the 6channel audio)

if you plan on using the onboard sound i would get a newer revision (any of the new boards at newegg will have the new revision, a refurbished one may or may not)
if your going to use a sound card then it really wont matter what type of onboard audio you have

 

[Jedibus]

If I decide to get the refurb of the 8k3a it's the OEM. I'll need to pick up some cables at least too right?

 

[Cuda1447]

Wow, boonesmi. I knew barely anything about overclocking, but that explanation has enlightened me ALOT! Thank you soooo much.

 

[LurkingInNC]

Thanks Boonesmi, good info for another first time system builder (me). How can I tell from the specs which boards have a 1/5th pci divider? Anyone with offhand knowledge as to boards with this feature?

Thanks.

 

[maverick24]

Boonesmi - thanks for the consise crystal clear post on overclocking...

i have a question - can u throw some light on memory:fsb ratios ???

i see this a lot: stuff like 3:4 multilpier and stuff - have no idea what that means....

i have an abit it7 with a 2.26 GHz P4 which i plan to overclock after i understand how to do it....


any pointers or urls would be much appreciated...

thanks

 

[Boonesmi]

Jedibus - sometimes the refurb boards at newegg come with all the cables, and sometimes they dont... if it comes as just the bare board all you will need is a floppy cable and one or two ide cables (you can probably find some pretty cheap at your local pc store)

LurkingInNC - i know the epox 8k3a+ has the 1/5th divider, and if i remember right the asus a7v333 does also... hopefully some other guys on here will read this thread and list other boards they know of. or you can read reviews of different kt333 boards to see which ones do and dont have the dividers... as a side note older via chipsets dont support the 1/5th and 1/6th divider, so i dont think you will get that feature on any board based on the kt266a/etc

maverick24 - ive not built a system with a pentium chip since my P1 166mhz so im not real familiar with overclocking the pent4... but my understanding is that the pent4 bus is quad pumped (4x) meaning its labled as a 400mhz fsb (which is actually 100mhz fsb quad pumped), or 533mhz fsb (133mhz quad pumped)

so my understanding is with a 3:4 ratio if you run a 100mhz fsb you will get 133mhz memory speed... or with a 133mhz fsb your memory would run 178mhz
obviously a 1:1 ratio would just means your memory runs synchronous with your fsb
a 4:3 ratio would give you a 133mhz fsb with 100mhz memory... etc etc

 

[Jedibus]

Thanks again Boonesmi! I think this thread deserves a sticky