Why no 200MHZ FSB?

[kbear2569]

I'm relatively new to OC'ing, but I've got myself a system that's running pretty well (see signature). I'm able to OC to 2.3G at 14*166 @1.7vcore with cpu temps at 42 idle/47 load. I am also able to bump the FSB up to about 175 without a problem (13*175), but any attempt to go higher results in a system hang once I get into windows. Ideally, I'd like to run my system at 12*200, since I've heard of others who have been successful. I don't think it's a heat problem since I'm stable at 2.3 with a 166 FSB. Also, I've tried bumping the vcore up to 1.75v (max for my mobo), the memory voltage up to 2.8v from 2.6v and the agp voltage up to 1.7v from 1.5v. Lastly, I've tried to adjust the memory timings from "aggressive" to "optimal", but still no luck. Any ideas? I heard I can mod my mobo to be able to increase vcore, but I'm not sure if I want to do that yet... Maybe my chip is as fast as it's going to get? By the way, my CPU is an axda1700dlt3c with JIUHB:0307VPMW.
Thanks.

XP1700 TBred-B @ 2.16G (166*13)
Noise Control Silverado HSF
ASUS A7N8X
2x256MB OCZ EL PC3500 DDR
ASUS GeForce3 Ti200
300 Watt PSU
45G IBM 7200
Windows XP Professional

 

[svol]

Well ofcourse not all T-breds will reach 200 MHz FSB... but there are ones that do. You just have to got the good core and some luck.

Anyway another thing it could be is northbridge overheating. The northbridge gets pretty hot around 200 MHz so you might need to cool it better.

Another explanation could be that your 300W PSU can't supply the system with enough power.

My dual-PSU PC is so powerfull that the neighbourhood dims when I turn it on

 

[vk2amv]

I would be blaming the RAM. That specific CPU stepping you have there is one of the better ones. OCZ has a loooong history of their RAM not doing its rated timings/speeds. Try changing the CPU to RAM speed ration to 50% and see if you can get 200Mhz FSB at a 10x multiplyer. That will only have the RAM at 100Mhz but it will prove if it is the RAM causing the problem or the CPU just at its limit. Or maybe something else it limiting you. Make sure you have the AGP speed locked to 66Mhz too.
AREA_51

'It's only when you look at an ant through a magnifying glass on a sunny day that you realise how often they burst into flames'

 

[kbear2569]

Thanks for your help. Well, I tried running my cpu at 200 fsb with my memory at 100 and it worked fine. I was able to keep the fsb at 200 and increase memory to 133, but no higher. I guess it could be the RAM, but I'm also able to run my fsb at 166 and my memory at 200 with 5-2-2-2 timings. I just can't seem to get the RAM and fsb to run synchronously at 200 MHz. Oh yeah, I did make sure the agp speed was fixed at 66.

I think I will try upgrading my PSU next, since I do get random reboots when I try to push the fsb/mem to 200.

By the way, do they sell fans for the A7N8X heatsink on the northbridge? Also, reccommendations on PSU?

Thanks.

XP1700 TBred-B @ 2.16G (166*13)
Noise Control Silverado HSF
ASUS A7N8X
2x256MB OCZ EL PC3500 DDR
ASUS GeForce3 Ti200
300 Watt PSU
45G IBM 7200
Windows XP Professional

 

[LtBlue14]

sounds like your power supply. it's a generic one too isn't it? get a new one. enermax EG465 (431W) or antec true power 430W
as for your northbridge, <A HREF="http://www.newegg.com" target="_new">http://www.newegg.com</A> has passive zalman northbridge coolers for $6 plus shipping, if you're in the USA.

<A HREF="http://www.tweaktown.com/document.php?dType=guide&dId=120&dPage=1" target="_new">WinXP tweak guide</A>
<A HREF="http://www.tweaktown.com/document.php?dType=guide&dId=145&dPage=1" target="_new">WinXP tweak guide 2</A>

 

[kbear2569]

Thanks. I'll go ahead and order that stuff. Hope it works!

XP1700 TBred-B @ 2.16G (166*13)
Noise Control Silverado HSF
ASUS A7N8X
2x256MB OCZ EL PC3500 DDR
ASUS GeForce3 Ti200
300 Watt PSU
45G IBM 7200
Windows XP Professional