1700 Overclock to 2.5 on air Need help with stability

I just got my 1700+ T-bred DLT3C 0319 up to 2.5ghz. But I'm haveing stability issues. Here's what I've got:

1700+ T-bred DLT3C 0319
NF7-S ver 2.0 mb
512 Corsair XMS PC 2700 (1 stick)
SLK 900-U w/Smartfan 2 (max rpm's)
80 gig WD 8mb HDD
GeForce 4 Ti 4200 64mb 8x
Lite On 52x24x52
500 watt Achieve PSU

I have the fsb set @ 218, x11.5 multiplier, 1.75 v-core. My temps are 25c mb, 41c cpu. So I don't think it's a heat issue. Here's my psu rails:
+3.3 @ 3.33, +5.00 @ 5.03, +12.00 @ 11.49 (sometimes under full load it will drop to as low as 11.37v, the +3.3 & +5.00 rails stay about the same under load).

Any ideas on what I need to do to get this thing stable? I know I could drop the multiplier, but then I won't be able to get 2.5ghz. I'm a little worried about my psu. Anybody know if Achieve psu's are any good?

Definitely increase the vcore. Your stepping is very very good, but the average DLT3C still needs in the ballpark of 1.9v to reach 2.5ghz with stability. Secondly, your 12v rail looks very low. I'd heavily suggest investing in a name-brand PSU; an Antec True430 would be my top pick for a system like yours. Your current Achieve does not have the quality or power to sustain such a high-level overclock.

I think you are probably right on both counts. I haven't oc'd the mem yet. Think that may help? If so, what would you suggest?

BTW, How much would an Antec True430 cost? I've been very skeptical about that psu (the Achieve psu) from the beguning.

Thanks

Memory not overclocked? Are you running async? If so, I'd change the ratio back to 6/6, as anything else can hurt performance and overclockability. But deal with them seperately. Reach your highest possible clock speed, and then refine it by reaching it a high fsb/memory frequency. The Antec is $80. You could try a 350w fortron for $32, if money is an issue. I've reached 2.5ghz with my 300w Fortron, but both of these probably will not be too future-proof.

Are you running async?

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Please excuse my ignorance, but I don't know what "async" is. Could you enlighten me? I just got this NF7-S board, still trying to figure out all the great oc'ing features. Any sugestions on a good starting point for mem voltages, settings?

On the Antec psu, I just checked Newegg. They have the Antec True430 for $80 also. But as a "Back to School" special they have the Antec True480 for $87.00. That sounds like a good deal. I think that I may just have to buy that. That would probably solve most of my problems. But yes, money is an issue, going to have to dig deep for this. But as you said, they aren't going to be very "future-proof". So maby I can buy a little more time with the 480.

Async is running the front side bus and memory bus out of sync. I'd suggest that you set the ratio to 6/6, to keep them in sync. Drop your multiplier to 5.0x, increase the memory voltage to 2.9v, and then see how far you can push the front side bus. Make sure that you enable CPU Interface, and disable all spread spectrum options. 6-3-3-2 is good starting point for memory timings. Tighten or loosen them as needed later on. Once you max out the front side bus, then increase the multiplier and core voltage.

My biggest problem is the CPU interface! I can push the cpu much higher with cpu interface disabled.
Also my ram doesn't like voltage over 2.7. I can run it on 440Mhz at stock voltage. With 2.9 i get a lot of errors.

Antec are great PSUs, but the ThermalTake 430W with Active PFC is also a great model. It's manufactured by SirTec.

Async is running the front side bus and memory bus out of sync.

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Doh, I should have known that.

Drop your multiplier to 5.0x

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Do you mean to drop the multiplier from 11.5 all the way down to x5.0? Why so low?

So that the CPU internal speed is not a limiting factor of your FSB/mem overclock

Ok, I see. Thanks. I went ahead and ordered the Antec True480 psu. It should be here by next Wednesday. I'm very anxious to see just how much of a difference a quality psu will make. I think that will solve most of my stability problems.

Did you raise the vcore first though? It's not going to do 2.5 at that core voltage.

you need at least 1.85v to get it to run stable at 2.5Ghz