Just thought I'd share a bit of my AthlonXP overclocking experience with you gents:
Some of you might know I'm clinging on to a 2+ year old K7S5A motherboard... a budget bottom-end offering from ECS even way back then, single channel 266 Mhz DDR, not compatible with 333fsb athlons because they weren't even available yet...
The reason I still have this beast is because I'm holding on until the 939 pin Athlon64 mobos are out. So naturally, as I get closer to buying the new kit, I take more and more chances with my old rig, trying to squeeze every Mhz of performance out of it.
Overclocking on my motherboard is limited to FSB with a modified BIOS: the mobo doesn't support multiplier changes, even if the CPU is unlocked.
Another reason the mobo sucks for overclocking is that the AGP and PCI busses are not locked; when you raise the FSB, you raise the bus speeds as well, which can crash the system even if the CPU is doing OK.
Anyway... I scored a 2400+ a while back basically for free, which is 1995 Mhz or so stock (15 multiplier x 133 Mhz). Worked fine at 143 fsb (15x143= 2145 Mhz), the CPU still ~40 degrees with a Coolermaster Aero7+. The only real problem being that the AGP bus is stressing the videocard, so my Radeon overclocks go down.
I really want 2.2 Ghz, so I tried 147mhz fsb (147 x 15 = 2205). My success is... limited. Even though the CPU is still running cool as a cucumber, and can run stress tests all day long, once I run a game: crash to desktop. The damn AGP bus is too high for the videocard. Damn, damn, damn.
So I figure, damn, the CPU is doing fine, but the machine can't handle the AGP bus speeds. Now if I could just raise the multiplier to 16 instead of 15...
It turns out, the 2400+ and 2600+ have the exact same voltage, the only difference being the multiplier is 15 on the 2400+ and 16 on the 2600+. So I look into it and, my god, it's the simplest mod in the world! Only ONE of the L3 bridges on the CPU has to be severed! Too easy! Ha HA!
Any of you ever etch/connect the L3 bridges on an Athlon chip? heheh. I mean, holy CRAP are these things ever tiny! Like so tiny my sharpened Xacto knife *edge* is about 1/3 of the width of the distance between the separete bridges!
Not to mention that, but on the thoroughbreds, the bridges are under the surface of the packaging, so I have to scrape it off until I see metal. And on the 2400, I have to scrape a bridge that is between 2 bridges that must remain intact.
I don't think you can appreciate how small these things are until you see them. It might not sound like a big deal, but I don't even have a magnifying glass, and it's basically like trying to cut an individual human hair with a knife while making sure you don't sever two other human hairs within a hair's width of the one you are trying to cut.
Nevertheless, armed with bravery, stupidity, and luck, I planted myself at the kitchen table and began the precise work. How deep do I scrape to make it deep enough to sever the bridge? How deep is too deep and would destroy the processor?
The answer in my case was about half a millimeter. I can't describe the anxiety and apprehension I experienced when I plugged her in and fired her up for the first time. It's stupid insignificant events like this that idiots like me live for.
As you can see by my sig, the operation was a success! The CPU is now clocked at a healthy 16 x 138fsb, or 2208 Mhz (roughly the equivalent of a 2750+ rating).
I know it doesn't sound like much, but hey, it made me happy. I'm easy to please I guess.
At 143fsb it doesn't boot, I guess 2288 Mhz is too much for the old beast.
They better release those socket 939 mobos before I do something really stupid... like cut and fill more bridges to change the voltage...
I can totally relate to your post. My old system was a K7S5A / 2100+ / 9500Pro, and I was doing the little 3DMark competition with Grape Ape. He kept overclocking his system, and beating my score, and I couldnt overclock anything except my video card. I didnt have the cheapo-mans bios or anything. I'm unfortunately still using that cursed DDR266 memory and 2100+ from my old motherboard, but I have it clocked at 2.06ghz on an nForce 2 chipset.
Thanks for sharing your success story....dont blow anything up
lol. Im trying to squeeeeeeeeeze everything i can out of my system. But my stupid Generic ddr400 is holding me back (wont even do 202mhz (404ddr)). So im trying to find out how to volt mod my XFX5600FX(Pine) Graphics card.
I prefer the wire in socket mod but I've done both. Cutting wasn't so bad but I used an 8X magnifying glass. I don't know how you did it with bare eyes.
What kind/brand of conductive paint did you use to close bridges?
I want to turn my Tbred into a mobile so I can access the soft multipliers. I want to try them so I can attempt at illusive 14X multiplier on a legacy (VIA KT133A) motherboard.
Last time I painted bridges was on my Tbird but back then I used automotive defogger repair paint and this stuff is too viscous to use on XPs.
I orginally used one of the wire workarounds to enable 14X, described at John Carcich's website (now defunct). It worked great for about 8 months then suddenly just stopped. Redoing the wire mods yields nothing. I can still set multipliers 15x thru 23x (24x is too high an OC) but 13x thru 14x are unavailable. The problem was documented at John C's site, something to do multiplier handling of legacy processors and northbridge timing.
Soft multipliers probably won't get me past the above problem but I want to try it anyway.
<b>56K, slow and steady does not win the race on internet!</b><P ID="edit"><FONT SIZE=-1><EM>Edited by phsstpok on 05/28/04 11:30 AM.</EM></FONT></P>