First attempt at OCing

I just had my first go at OCing my system:

Default setup:
P4 3.2g Prescott
Multiplier: 16x (locked)
CPU mhz: 200mhz
PC3200 400mhz RAM 2.5-3-3-8
RAM voltage: 2.75v

OCed state:
3.5ghz
CPU mhz: 219mhz
RAM/CPU ratio 1:1
RAM: 2.5-3-3-7 (my pos RAM won't go lower)
RAM voltage: 2.85v

PC seems to be running ok, using benchmarking tools in PC Wizard 05 it seems to have made a fairly noticeable impact on performance.

Just wondering if I have done anything that could be potentially dangerous here? Looking in my BIOS the next step up in RAM mhz is 533mhz, so I just left it at 400mhz.

 

Before OCing
Processor
Addition/Multiplication (SSE) : 4198.54 MFlops
Division (SSE) : 756.14 MFlops
Square Root (SSE) : 766.58 MFlops
Addition/Multiplication (FPU) : 1713.67 MFlops
Division (FPU) : 70.85 MFlops
Square Root (FPU) : 70.9 MFlops
Whetstone : 462 KWPS
RAM
Bandwidth (Write Float) - Prefetch) : 884.95 MB/s
Latency : 98 ns (312 cycles)
Bandwidth Efficiency : 79%

After OCing
Processor
Addition/Multiplication (SSE) : 4607.86 MFlops
Division (SSE) : 829.8 MFlops
Square Root (SSE) : 839.21 MFlops
Addition/Multiplication (FPU) : 1875.28 MFlops
Division (FPU) : 77.65 MFlops
Square Root (FPU) : 77.77 MFlops
Whetstone : 503 KWPS
RAM
Bandwidth (Write Float) - Prefetch) : 969.35 MB/s
Latency : 96 ns (337 cycles)
Bandwidth Efficiency : 75%

These figures look ok?

 

Dont run your Tras ( the last timing ) any lower then the sum of the other timings your risking data coruption exa... 2.5+3+3=8.5 so dont run a Tras of 9 or less I learned it the hard way http://forums.majorgeeks.com/images/smilies/wink.gif....Nice OC BTW you cant get any more FSB out of it ??? what core voltage are you running ??

 

I dont mean to butt in.

Does the same apply for a PC running stock speeds?
Got any more detailed info on the subject?

Thanks.

 

I dont see why it whouldent....The Tras is the max time a page can be open and if the 3 other timings arn't complete before the Tras time the page is forced to be reread making the system slower ( and in some cases if the page is close to being done the system will forget to reread the page causing data curuption ) so iv read... I donno exactly how it works but the best analogy i can think of is reading a page in a book and having the book slamed shut in your face when you almost done with the page...

 

I read here that tRAS should be a sum of tRCD, CAS, and 2. In my case, that would be 2.5 + 3 + 2 = 7.5 I don't have 7.5 in my options so I thought I'd drop it to 7.

I haven't tried to overclock it further as I didn't want to go too far on my first attempt at overclocking. Is 3.5g at the above settings safe? CPU idle/load temperatures haven't increased at all, so I guess I'm more worried about dying RAM!

 

I've cranked tRAS back up to 8, should be kewl I think

Currently running 1.375vcore, according to recommended voltage range for my processor (3.2ghz prescott) I shouldn't run higher than 1.4 so I've left it as such. Not too sure what you meant re: FSB? Current FSB is 876mhz, based on 4x 219mhz. Probably can crank more out but didn't want to take the risk of overdoing it. At current settings, hasn't given me any problems yet - no lockups or any unusual behavior.

More opinions, comments, suggestions?

 

Just decided to take the leap of faith and raised FSB to 900mhz giving me 3.6ghz. Temperatures at load and idle haven't changed at all, so I guess it should be ok.

Processor
Addition/Multiplication (SSE) : 4709.83 MFlops
Division (SSE) : 853.44 MFlops
Square Root (SSE) : 863.34 MFlops
Addition/Multiplication (FPU) : 1861.45 MFlops
Division (FPU) : 79.76 MFlops
Square Root (FPU) : 79.72 MFlops
Whetstone : 519 KWPS
RAM
Bandwidth (Write Float) - Prefetch) : 990.41 MB/s
Latency : 96 ns (345 cycles)
Bandwidth Efficiency : 75%

 

Hmm, question for you ace; how come im running 2.5/3/3/8 without a problem then if what you say is true?

 

If you read this: http://www.ocfaq.com/article.php/overclocking/63

I think tRAS should be a sum of tRCD, CAS, and 2.

That is, 2.5 + 3 + 2 = 7.5 in our case.

 

I think its less of a prob on intell mobos too ....

 

I'm running 2-3-3-5 on an nvidia nforce 3,with no stability probs!

 

Hmm interesting maybe its only a prob with NF2 mobos then.... all the NF2 mobos iv had get slower (compared to a Tras of 9 or higher) and/or get data curruption with a Tras less then the sum of the other 3 timings.......come to think of it i had a VIA socket A mobo do it to ...

 

Nice little article,so it seems I could be lowering performance by having a low tras,but not noticing it,I'll have to do some benching see if I can spot it,it took me awhile to see it in the article.

 

Got me woundering.
Have NF2 mobo running 2.5 3 3 7, all seems good, now need to test alittle & see.
Ive seen several PC's mem running auto set/SPD with low tras, on NF2/Intel & I think a KT600 chipset.