Cant get past 225 FSB

[akassasin]

I lowered the HT multiplier to 4x and set the RAM speed to 166 mhz and I get a blue screen/reset right when XP begins to load with anything over 225 FSB.

I messed around with some different RAM voltages but nothing worked
On startup it says my processor is around 2500 mhz and RAM is 380 mhz

Any suggestions? Could it be related to memory timings?

(computer specs in sig)

 

[ty1er]

Well if your running your ram divider at 166, then bumping up your HTT to 225. Now your ram should be running only at 187mhz. So you shouldnt be having any problems due to memory, since its running below the stock specs.

Im not familar with the Nforce4 chipset for the 939s, but maybe you have to enable the PCI/AGP lock from in the bios?

 

[Traire]

Make sure if your using SATA that your plugged into the right ports. Not all of the SATA channells are are always locked. Try switching channells and see if that helps.

 

[Soulkeeper]

i wouldn't expect too much with that Value select, these A64 motherboards are extremely low latency and put a good deal of stress on the mem, especially if yur running 1t.
wouldn't surprise me if the mem is topping out at 180-210
could try pushing more vdimm
one of those divider/mem combinations should find you a sweet spot
generally speaking tho the mem running under 200 isn't gonna hurt you too much on yur setup as long as everything else is primed
i've encountered similar bios compat/pickyness with nforce2/i875
does enabling/disabling spread spectrum and/or using the exact timings recommended by the mem/board maker for yur particular setup get you any higher ?


good luck

 

[thriemus]

I use all of the following and it works a treat:

mem voltage 2.7
vcore 1.5 in mobo bios
pci lock 33.3333
htt 4x
bus speed 241
multiplier 11x

Try it and see if it suits your system

Sandra has my system running faster than a 2.6 ghz opteron with 1 mb L2 cache.

 

[akassasin]

I can overclock the ram to 450 mhz on a 1:1 ratio, but when I change the ratio to 5:6 (166 mhz) I cant get it past 381 mhz without windows crashing at startup. (both at stock timings and 4x ht multiplier)

Is it possible the memory would have problems running at a 5:6 ratio or is it something else causing windows to crash?

By crash I mean blue screen with IRQ_NOT_LESS_EQUAL or something like that at the top.

 

[dfedders]

Originally posted by: akassasin
I lowered the HT multiplier to 4x and set the RAM speed to 166 mhz and I get a blue screen/reset right when XP begins to load with anything over 225 FSB.

I messed around with some different RAM voltages but nothing worked
On startup it says my processor is around 2500 mhz and RAM is 380 mhz

Any suggestions? Could it be related to memory timings?

(computer specs in sig)

Lower the multiplier for the CPU in the bios so it is running at a slower speed, and see if you still have issues raising the FSB.

 

[akassasin]

ive tried that. I think its called "Hammer fid control" in my bios. If I set it to anything but auto the computer wont boot and I have to clear cmos.

 

[thriemus]

I had similar problems with the value select memory until i set the voltage to 2.7, also this ram is not capable of 1T and disable spread spectrum.

Also, try running memtest right after changing any settings to rule out ram.

 

[akassasin]

I have it set to 1T though and it works. Forgot to mention, voltage is already set to 2.7 and spread spectrum is disabled.

 

[thriemus]

Have you confirmed this using memtestx86 or memtestx86+ or microscope? If so how many passes?

 

[Mrvile]

lol clearing CMOS, I use to do it all the time when I messed around with my own OC. The worst part is setting the clock back to the right time.

Anywho, that 380mhz is about right. Since it runs at about 187, the memory is DDR, so the frequency is doubled, so 380 would be dead on.

 

[akassasin]

All I know is I set it to 1T in the bios and it booted up without a problem. Its running Prime95 right now and when I get home from work I'll try memtest.

 

[thriemus]

Originally posted by: Mrvile
lol clearing CMOS, I use to do it all the time when I messed around with my own OC. The worst part is setting the clock back to the right time.

Totaly agree! it annoys my head!

 

[akassasin]

Originally posted by: Mrvile
lol clearing CMOS, I use to do it all the time when I messed around with my own OC. The worst part is setting the clock back to the right time.

Anywho, that 380mhz is about right. Since it runs at about 187, the memory is DDR, so the frequency is doubled, so 380 would be dead on.

But considering the fact it runs ok at 450 mhz 1:1, doesnt it seem a bit off that I couldnt get it above 380 on a 5:6?

Either way, no matter I approach it, I cant get my CPU above 2500 mhz. People are getting that with there 3000+'s so something is not right.

 

[thriemus]

I run my memory at 378 and the only benchmark it will _really_ affect is Super Pi. All other applications that arent memory bandwidth limited will run at blazing speeds

EDIT: I just noticed from a sig that my system outperforms a 3.9 ghz water colled p4 in 3D Mark 2003with similar video card and much faster ram. RAM speed although important is not the be all and end all of system performance.

 

[akassasin]

RAM speed isnt my goal here though, CPU speed is. Im just thinking that the RAM is the limiting factor here. I think that the fact that my FSB wont raise above 225 is due to the fact that my RAM wont raise above 380 mhz 5:6. This, in return, limits my CPU to about 3500 mhz.

At a 1:1, though, it seems to be decently stable with a straight 225 fsb 4x ht with:
ram: 450 mhz
cpu: 2475 mhz.

i guess I can live with that
Im probably just missing something though... im very new to this.

 

[akassasin]

Is there any downside to flat out overclocking ram without changing the ratio?

 

[thriemus]

Well yes, in that your ram will be running slower, however the positive side of the trade off will be system stabilty. I have to remember to reboot this system. In all seriousness I never switch my machine off, ever. Stabilty is paramount in my opinion

 

[Mrvile]

Wait a minute, didn't you say that you can do 450 no prob on 1:1? That's really weird, how your ram can't do anything higher than 380 on 166...try loosening timings to like 3-4-4-10, AMD doesn't have a prob running with loose timings.

 

[akassasin]

Originally posted by: Mrvile
Wait a minute, didn't you say that you can do 450 no prob on 1:1? That's really weird, how your ram can't do anything higher than 380 on 166...try loosening timings to like 3-4-4-10, AMD doesn't have a prob running with loose timings.

Yeah, thats whats confusing me

ill try that

 

[thriemus]

Bear in mind that an A64 (on NF4 platform) system memory bandwidth is fastest using a tras of 6-8.
Also that slower Mhz can bring real system stability I believe that akassasin should be happy with 380 Mhz ram speeds. I know I am for now untill I can get 2x 1 GB sticks @ DDR 500 5-2-2-2 1T then these 4x512 MB goto my Linux box.

 

[akassasin]

So far these are my 2 maxed out configurations:

#1
FSB: 225
RAM: 1:1, 450 mhz
CPU: 2475 mhz
HT: 4x

#2
FSB 230
RAM 5:6, 380 mhz
CPU: 2530 mhz
HT: 4x

Raising the FSB higher for any either of these configurations results in windows crashing upon startup.

Which one should I use?

Or any other suggestions on how to get my FSB up any higher on the 5:6? (will try lower mem timings tonight)

 

[thriemus]

What cpu Voltages are you using? I had terrible problems until I upped the voltage.

 

[akassasin]

I havent gone higher than 1.550