Opteron 146 overclock - where to go from here...

[scrandman]

What stepping is the chip btw?

Its a CAB2E 0602GPKW.

(I think you were asking me, right?)

[Fat Gat]

I've got CAB2E stepping, its sat at 2.95 GHz now. Used to be able to hold this at stock voltage but now its having to draw 1.45v up from 1.4v. Have had it at over 3 GHz but it really doesnt seem to appreciate been made to run that fast!

BSODs everywhere!

[The Codfather]

Hope you don't mind my invasion..

I have an Opteron 148 CACJE stepping, I'm willing to OC but I'm not really sure where to start. I'm running an Asus A8N SLI-Deluxe board and 2GB of RAM (4x512MB sticks, 2x Corsair and 2x Geil both running 2-3-3-8 quite happily together)

I've read up a bit and -ChEm- has offered me some info so I know that it's mainly down to the HTT as far as getting the speed out of it, but it's the memory timings that worry me, I'm not sure how well I'll be able to do with 4 sticks. It seems most OC's I've seen people are running 2x 1GB or 2x512MB sticks as they can keep the timings tighter with lesser RAM. If anyone wants to lend a hand I'd be glad.

I'm not sure I want to start messing about and toast this chip, I've already had to shell out for a PSU dying a premature death due to circumstances unbeknown to me :/

Just you don't think I'm a complete idiot, I've been building PC's for about 5 years now, so I usually know my stuff when it comes to hardware, I've just never ventured into OC'ing before now.

[-ChEM-]

dont worry about timings, im running 4x512 at 2-2-2 (the main thing is that theyre at 2T instead of 1T unless i lower it to below DDR370 which is a shame)

you should be able to leave it all on auto but you can also just raise it to 3-5-5-10 until youve finished OCing... leave it on 2T (aka "command per clock = disabled") and a big divider (133mhz/DDR266 should do it) and it wont give you any problems, you can bother with memory once youve got the cpu done

if i was you id drop the cpu multi to 5x (for 1.5ghz cpu speed) and the LDT to 3x (for 900mhz HT bus) first and clock the board up to 300mhz HTT, you shouldnt need to change any voltages or anything

run prime for a while to test it, then you know the motherboard is ok for it

start putting up the cpu multi and see how high you get and when you have problems, raise the voltage and try again... those cacjes are pretty good i think so you can expect to get to 300x9 on stock volts if its a good one

above 300HTT you will have to be more careful with the settings to make sure the RAM is still ok (and you should go slower then anyway as you might be reaching the moboard limit)

[The Codfather]

Okay, I set the CPU Multi to x5 now I have a 1GHZ Opteron. The RAM is set to 266 in the only RAM settings page I can find in the A8N bios. I can't find any mention of this LDT though and to make things worse I don't even know what LDT is

There's a setting they just call CPU speed I think where you can manually increase the HTT speed, I tried something little like 210 with the x11 multi and ended up with 2300mhz, but the RAM was then running at 135mhz according to CPUz..

I think I'm in way over my head here :/

[Edit] But I decided to fiddle anyway.

I increased the HTT to 300 and it looks something like this now;



I'm guessing the idea of this is just to see if the mobo can handle 300mhz HTT right? I'll run Prime for half an hour or so, increase multi and report back. I hope I'm doing this right...

Oh, I also set the Vcore for the CPU to 1.45, it was set to Auto in the bios and seemed to fluctuate a bit when I sat and watched CPUz.

[Edit-Edit]

Messed around a bit more, tried a Super PI 1M at the screen shotted settings and it gave back an error after loop 2 or 3, I clocked the HTT back down to 290 (Showing in CPUz as 292) and it passed the 1M no problem.

[Update]

Pair of Super Pi 1M's and 22mins of Prime95, no problems, upping multi.

[Update 2 - 00:30am]

1 hour later, Super Pi stable, 1M in 33 Seconds.



Just a little further to go now... Uber thanks -ChEM-, I wouldn't have been able to do this without your help

[Update 3 - 00:40am]

And so it was written. And so it was done.

http://img.photobucket.com/albums/v3...ther/Cpuz3.jpg

Quite pleased with myself for a first OC.. and now I hold both fear and respect for the Opteron 64, it's crazy what these things can do, all while idling at 32/34 no less. I may pull back on the HTT and see if I can get a bit of a higher overall clock, it seems to be unstable when the HTT is set to 300 (it's actually 299 in bios)
Many many thanks again -ChEM-

[-ChEM-]

mmmm the LDT is the multiplier that calculates the HT frequency

it will have been 200 (HTT) x 5 (LDT) but now the HTT is up i would guess it has adjusted itself down otherwise it would be nearly 1500mhz

it has no bearing on speed but it can cause problems if its too low or too high, most boards will do 750-1100, and the very new ones can go up to 1500 (but i dont think that includes those asus ones)

i hope that helps to identify it in the bios, it usually goes from x3.0 to x6.0, you might be able to go above 300HTT if you can set it manually

if you cant youve got the 10x CPU multi to use anyway so the extra for a 148 might have been worthwhile... having a high HTT wont improve things so you can change to 10 x 268 and it wont be any different to the settings you posted above, the only important thing is that you only have certain RAM divders and you dont want an HTT that cant give you decent memory settings (be that too fast to have good timings or just too slow)

if you get worried just start with the cpu speed then after that make sure you have fixed the settings to:
-set the cpu voltage how you want it and not higher than 1.55v
-kept the HT between about 750mhz and 1100mhz
-kept the RAM timings high enough for them not to interfer or screw up the ram
-used a divider that will keep the RAM in spec although high timings should ensure it wont be a problem if its overclocked (check CPUz if youre edging high as the maths is funny)

thats all you need to worry about, unless you want to push the RAM or fiddle with drive strengths and chipset voltages to get a better HTT or cpu clock, and thats all for later anyway

[The Codfather]

I ran through a few Super Pi 1M's and a complete 3D Mark 03 and I know it's 100% stable at 2.97GHZ (292HTTx10) I continue to be amazed by this chip. Nice to know I have my stable to fall back onto whenever I don't feel like messing about.

I just ran through a few Super Pi with 274HTTx11 = 3019mhz (in CPUz) and it seemed to be rock, so I'm going to leave it to run Prime overnight with those settings. To be honest I'm overjoyed at 2.9 that's amazing in itself for a 2.2GHZ chip, but if I'm able to run it at over 3GHZ stable on just air cooling....

Stunning.

[-ChEM-]

if you get over 3ghz you immediately become a better person than everyone else and are allowed to slap them as you see fit

[The Codfather]

if you get over 3ghz you immediately become a better person than everyone else and are allowed to slap them as you see fit

http://img.photobucket.com/albums/v3...ther/Cpuz3.jpg

It'll do Super Pi no problem, but it's not Prime stable unforunately. I'm sure 3.0GHZ stable will be possible though, it has no problem whatsoever in 2.97GHZ and is solid as a rock. I'll try it tonight at as close to 3.0 as I can possibly get seems a shame to only be 30MHZ away from a stable 3.0 >__<

Current stable settings;



Completely Prime stable, 30s 1M in Super Pi and ran an entire 3D Mark 03 problem free. <3 Opteron 148

Interesting figure here too;

3D Mark 03
AMD Opteron 64 148 @ 2.2GHZ
7900GT @ 470/1370

ALL STOCK SETTINGS

=16265

AMD Opteron 64 148 @ 2.97GHZ
7900GT @ 528/1612

=19266

I think for the time that's been put in and the money that's been spent theres an amazing amount of potential that's been unlocked here.... and I haven't fitted my Zalman to the 7900GT yet so possibly more to come from that.

Oh, I did find the LDT setting, obviously being completely dumb and new to this I didn't notice the big setting that said "HT Frequency" it's set to auto at the moment. Hopefully if I fix that at x5 and increase voltage to 1.5v I can get a completely stable 3.0 that'd really make me happy.

[-ChEM-]

no thats too high, its supposed to be 1000mhz for those chips or 800mhz for the early ones so get it in that kind of range

[The Codfather]

I'm lost again..

I'll probably just leave it at 2.97, that's more than enough for me and seems to be stable as anything.

[-ChEM-]

ok ill go slower, all you need to know is that the hyper transport bus is a bus that needs to operate between 800mhz and 1000mhz (although it will still work outside those values within reason)

the old fsb used to run data between the cpu and the memory controller but A64s have the memory controller as part of the chip so the fsb no longer exists as we know it

now it is called a hyper transport bus and it runs data between the cpu and southbridge (pci, pci-e, usb, ide etc) so really the only burden is the pci-e bus containing graphics cards... but still its got plenty of bandwidth to do that probably even at 500mhz now that the memory controller is out of the picture... so you just need to get it to a stable value, and that must be a value which is not too fast and not too slow

and as the chips were designed for 800 or 1000mhz, that is the obvious reliable choice

that basically means if you have HTT >265mhz go for 3x LDT, if its <265mhz go for 4x and if youre at stock speed it will be 5x

[The Codfather]

Okay I get you now. Thanks

I'm lucky it's been set to auto all this time then or I probably would have cooked it earlier >__<

I feel stupid asking so many questions, but how else will I learn eh?

[cptwhite_uk]

You're getting there...great overclock you lucky git

[The Codfather]

Hehe, thanks

I had a good play around last night, 2 hours of Battlefield 2, some Half Life 2: Lost Coast, CD Ripping, general browsing and then left Prime95 to run overnight. All absolutely flawless, rock solid stability.

I'm wondering if it's worth doing a little more messing to get to 3GHz stable just to say I'm running at 3GHz (I really doubt the extra 30MHz will provide much of a performance boost.)

Also the RAM. I'ts currently running at 2.5-3-3-6 @ 198Mhz (according to CPUz) I've really noticed no difference in performance from the old 2-3-3-6 @ 200Mhz and the RAM is currently being handled automatically by the board. Would it be worth (and is it possible) trying to get it running back at 200Mhz and stock timings or should I just leave things be for now?

[-ChEM-]

well you can put it down to 2-3-3, the 2mhz probably wont be enough to go below stock timings but theres no reason to let the board run it slower than it should be... you might be able to get it to 2-3-2 too depending on the luck of the draw... you would have to be some kind of freak to notice the difference but you may aswell do it for another 2fps or something, just drop it and run memtest for a while, if it doesnt work put it back, dont do it until youve finished with the chip though

and dont try and change it to exactly 200 unless you have serious OCD, that really is a load of hassle when youre trying to balance the htt for a max overclock, and its not possible anyway without dropping the multi down

and if you have an nforce4 board you will be better off with x-x-x-7 than x-x-x-6

6 is too fast for it to refresh in time so it ends up wasting the cycle sometimes... all the other timings should be as low as they can be though, you never know you might even end up with faster ram at 2-3-3-7 than the nubbies who run their expensive ram at 2-2-2-5 because of that

x-x-x-8 for ati chipsets, x-x-x-11 for nforce2 too btw