Hey all,
Recently ive started trying to overclock my old rig- here are the specs:
AMD Athlon XP Barton 2500+ (currently running at 12x180mhz up from 11x166, stock Vcore)
Asus A7N8X-X rev. 2.xx with latest certified BIOS (1010)
2x512mb pc3200 nanyatech ram (optimal timings for 200mhz performance is 3T-3-3-8)
Anyway, increasing the multiplier is no problem. The highest ive tried has been to 12.5- the equivalent of a 2800+, and on the stock vCore setting. Now, this gave me the impression that i have alot of overclocking headroom for my CPU. I started nudging up the FSB, maxing out at 12.5x182mhz with a Vcore of 1.675V (1.65V boots, but doesn't last a minute in prime95).
Going further, however, turned out to be a disaster. No matter what the multiplier, no matter how loose my ram timings (i tried 3-4-4-10), no matter what the vCore or DDR voltage, i can't get past an FSB of 182mhz.
This would be understandable if my motherboard was a revision 1.0x, designed for pc2700mhz ram and an FSB of 333mhz, however the a7n8x-X, on the box front clearly states:
"Ready for the latest generation of 400mhz CPUs!"
Checking out other articles/reviews, people have had no trouble pushing the a7n8x-X to 220+mhz fsb.
In somewhat a bold attempt to establish that the problem was either the ram or the northbridge (motherboard), i set my FSB to 166mhz (stock) and the DDR ram to 200mhz asynchronously (ie, i set it to 120% of the FSB frequency). I mean, theoretically, both my nforce2-400 northbridge and my pc3200 ram (at stock timings and voltage) boast support for 400mhz operation.
I couldn't even POST.
My comp kept making prolonged beeping sounds, and wouldn't boot, so in the end i had to waste another half hour resetting the CMOS.
Anyway, i guess i have pretty much concluded that the fault lies with the chipset- no matter how loose my ram timings, an fsb of 183mhz won't boot.
Also, i cannot modify the northbridge VDD voltage through the BIOS, so i guess thats an uncontrollable variable.
Does anyone have any advice as to why my chipset isn't functioning as it is made to? Feeling the northbridge cooler, it seems quite hot, indicative that the chip is making pretty good contact, so i guess heat isn't an issue (however im prepared to buy and apply some arctic silver paste if that will help). Also, its a passive heatsink- you think perhaps i need a larger CPU fan to cool the northbridge aswell?
Also, can anyone shed any light on the "Uber BIOS" that ive read about on some other forums? Apparently it allows higher FSB's to be set, but i'm not really sure about its credibility.
Thanks in advance for any help or support- i really, really would like to take advantage of my CPU's potential (i mean, if it can run at 12.5x182mhz with a 1.675 voltage, i would expect 11x200 to be in order with some voltage increments).
Recently ive started trying to overclock my old rig- here are the specs:
AMD Athlon XP Barton 2500+ (currently running at 12x180mhz up from 11x166, stock Vcore)
Asus A7N8X-X rev. 2.xx with latest certified BIOS (1010)
2x512mb pc3200 nanyatech ram (optimal timings for 200mhz performance is 3T-3-3-8)
Anyway, increasing the multiplier is no problem. The highest ive tried has been to 12.5- the equivalent of a 2800+, and on the stock vCore setting. Now, this gave me the impression that i have alot of overclocking headroom for my CPU. I started nudging up the FSB, maxing out at 12.5x182mhz with a Vcore of 1.675V (1.65V boots, but doesn't last a minute in prime95).
Going further, however, turned out to be a disaster. No matter what the multiplier, no matter how loose my ram timings (i tried 3-4-4-10), no matter what the vCore or DDR voltage, i can't get past an FSB of 182mhz.
This would be understandable if my motherboard was a revision 1.0x, designed for pc2700mhz ram and an FSB of 333mhz, however the a7n8x-X, on the box front clearly states:
"Ready for the latest generation of 400mhz CPUs!"
Checking out other articles/reviews, people have had no trouble pushing the a7n8x-X to 220+mhz fsb.
In somewhat a bold attempt to establish that the problem was either the ram or the northbridge (motherboard), i set my FSB to 166mhz (stock) and the DDR ram to 200mhz asynchronously (ie, i set it to 120% of the FSB frequency). I mean, theoretically, both my nforce2-400 northbridge and my pc3200 ram (at stock timings and voltage) boast support for 400mhz operation.
I couldn't even POST.
My comp kept making prolonged beeping sounds, and wouldn't boot, so in the end i had to waste another half hour resetting the CMOS.
Anyway, i guess i have pretty much concluded that the fault lies with the chipset- no matter how loose my ram timings, an fsb of 183mhz won't boot.
Also, i cannot modify the northbridge VDD voltage through the BIOS, so i guess thats an uncontrollable variable.
Does anyone have any advice as to why my chipset isn't functioning as it is made to? Feeling the northbridge cooler, it seems quite hot, indicative that the chip is making pretty good contact, so i guess heat isn't an issue (however im prepared to buy and apply some arctic silver paste if that will help). Also, its a passive heatsink- you think perhaps i need a larger CPU fan to cool the northbridge aswell?
Also, can anyone shed any light on the "Uber BIOS" that ive read about on some other forums? Apparently it allows higher FSB's to be set, but i'm not really sure about its credibility.
Thanks in advance for any help or support- i really, really would like to take advantage of my CPU's potential (i mean, if it can run at 12.5x182mhz with a 1.675 voltage, i would expect 11x200 to be in order with some voltage increments).