Why can't I overclock?

[BornStar]

I'm trying to overclock my 1600+ AGOIA but I don't seem to be having any luck. I think part of the problem is related to my RAM, but I just had a weird problem. I've been trying to get to a 166MHz FSB but that hasn't been working out for me, I know that's a RAM problem. I thought maybe if I knocked the CAS to 3, I might be able to hit a 152MHz FSB. Well, that kind of worked for me. It loaded into WinXP and everything reported 1600MHz for my CPU. Next I thought I might try to kick the CAS back down to 2.5, so I tried to reboot my machine to get into the BIOS and it just hung. It shut itself down and shut the monitor off but the fans were all spinning and both the HD and power LEDs were on. Does anybody have any idea what the problem might be? Is it possible my KT4VL just isn't up to overclocking? My system specs are under Lisa in my sig.

TIA

 

[Bovinicus]

Every component reaches a limit at some point. You just have to try and isolate which piece of hardware is the problem. It could be Add-on cards, the CPU, your memory, or your cooling could be improved to reach better results.

 

[BornStar]

Oh yeah, i forgot to mention what HS I have. I use a Thermalright SK7+ and then I've got a 4 LED fan from SVC (30cfm) on top of it. My CPU at full load is only 50*C. I noticed in Anand's review of the KT3 Ultra, he mentioned that it uses the CPU thermal diode but there's no mention of that anywhere that I can see for my MB so I don't know if that's accurate. I just really want to OC this thing.

 

[Necrolezbeast]

what kind of RAM are you using? You may also need to up the vcore and memory a bit...I have my 1600+ @ 1750mhz on a kt3 Ultra2 at 1.775v and 2.6v on memory on generic pc2100 @ pc2700

 

[BornStar]

I'm using Crucial PC2100 RAM. And it looks like the vcore is at 1.85 which seems rather high to me.

 

[Necrolezbeast]

I would back off the vcore a little bit to 1.8v or so...then up the voltage on the memory gradually to 2.6v - 2.8v and keep the timings at default or low. If you can get it to run stable(prime95/SETI/etc) try to increase the timings. I've heard people say SETI isn't a good program to test for stability and that prime95 is better, but SETI crashed within 45min where prime95 lasted 26 hours on my system, so I upped the voltages and have been running fine 24/7 with SETI for around a month.

 

[BornStar]

This is really strange. I was playing around some more and I can overclock to 151MHz no problem. I heard that the KT400 adjusts the ratio at 152MHz which is the only thing I can think of that might possibly cause this. Has anybody ever heard of this problem before?

 

[Necrolezbeast]

nope...never played around with a kt400...I was too cheap and went for the kt333, hehe

 

[BornStar]

Actually, the KT333 puts it in the same place. Or so I was told.