Overclocking E6 AMD X2 3800+

nshire

nshire

nshire

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I've never really done any major overclocking so just wandering for tips.

I've got Geil Value 1GB (2x512mb) DDR
Asus A8V Deluxe bios 1017
In Coolermaster Stacker original and has Arctic Freezer 64 cooler. And power supply aint a prob.
 
Well the more recent 3800+ X2s have been hitting up to 2.6Ghz on stock volts, and up to 2.8Ghz+ with a bit more Vcore.

Temps should be nice and low with the Freezer 64 Pro, great cooler. Would suggest limiting your volts to 1.55v maximum though. Max load temp I would say 55C per core. I usually go with that for the X2s. When running the CPU at stock volts, actually set it in BIOS, don't leave it on Auto. Above 200mhz FSB, drop the HTT multiplier to 4x. Over 250mhz FSB, drop it to 3x. Sorry if that's obvious; it's just something I always forget.

The GeIL value stuff should overclock a reasonable amount, but obviously stick it on a low divider and find the max CPU clock first. Remember with A64s, raw clock speed gives a bigger "real world" performance boost than anything else.

Try and get the RAM running 1T timing if you can, also gives a reasonable performance boost.

Other than that, give it a go and let us know how it goes!

Good luck ;)

Jon
 
Default vcore is 1.35v. As a starting point, I'd say whack the FSB to 240 and put your RAM on a 166 divider. This will give put your CPU @ 2.4GHz (shouldn't be a problem on stock volts) and the RAM @ 200MHz. Test stability for a few (8 is fine) hours using Prime95 or Orthos. If all is well, crank the FSB up some more but bear in mind that once you go over 240, you will start to overclock your RAM too so you might need to slacken the timings or as above, put it on a lower divider and see how high the CPU goes first before finding the right balance.
 
You probably won't even have to change the vcore. Your CPU will probably clock high enough to come up against the cooling limit of your cooler on stock volts. Extra vcore would probably let you clock higher, but will produce more heat. There is usually a lot of headroom in the late X2 3800s. Mine is stable at 1.35V at 2.65GHz, but I run it at 2.5 because of the memory. Your memory and motherboard might well indirectly dictate the most efficient overclock.

Using my system as an example:

At 2.5 (250x10), I can use a 5/6ths memory divider (which is inaccurately labelled as "166MHz" in some BIOSes) and have the memory at ~208MHz, which it is fine at.

At 2.65, which is the highest my CPU will do at 1.35V without failing a long S&M or Orthos run, a 5/6ths memory divider puts the memory at ~221MHz, where it fails severe tests and therefore isn't stable enough for me. I have to drop it to a 2/3rds divider, which puts it at ~177MHz, which isn't very efficient.

I could try something like 295*9 to give CPU of 2655 and a memory divider of 2/3rds to give memory speed of ~197, which would probably be the most efficient settings...if my board coped with a 295MHz "FSB", which it won't.
 
I run my E6 3800+ x2 at 2700MHz on 1.33v (1.35 set in BIOS) 24/7 with the RAM on the 166MHz divider so it runs at 225MHz (geil value PC3200 stuff) cas 2.5-3-3-5 it runs, but won't do CAS 2.0.
 
I got the weekend+Mon,Tues off and I will give my 3800+ a good go at. I be very happy if I got to 2.6ghz as its like the going rate.
 
just to inform you guys im currently doing 2.4ghz 240mhz x 10 HTT @ 4x (800mhz too a while to understand why some people said 4x other 800mhz) and memory at 2.5 3 3 5 as ghgh said and its at 1T. Just left it doing Prime95 atm and CPU at 49c mobo 30c.
 
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RAM Divider?

Is that the RAM divider by chance? like options such as 100/133/166/200MHz?

If it is then try setting it to 166MHz...if its currently set to 200MHz and your RAM is at a 1:1 ratio with the FSB and its stable thats pretty decent especially for geil value RAM. I got some geil pc3200 value stuff that can benchmark upto 250MHz but even one more MHz it wont run PI but is stable at 229MHz. (ive only got 2 x 256mb atm and this is the stuff that can do 250 for benchmarks) but I did have another 1024MB dual channel kit (2 x 512MB) that could not run above 225MHz with any stability - that was at 2.8v iirc.
 
i've got it at 166mhz i believe (at 177mhz? oc) (will have look later)
cpu2.6ghz.jpg
 
I think thats set to the 133 Divider as it would be more like 215MHz if it was at 2600MHz on the 166 divider off the top of my head I would have to check on my x2 but I run the 166 divider at 2700MHz and my RAM is at 225MHz.

what is your memory voltage set to?
 
I can only goto 2.8v too mate.

mine runs stable at 225MHz so it might be worth trying the 166MHz divider IMO. :)

HTH
 
ghgh said:
I think thats set to the 133 Divider
Click to expand...

It is indeed.

133 Divider:
200/133 ~= 1.503
259/1.503 ~= 172.3mhz - which is what you have at the moment.

166 Divider:
200/166 ~= 1.205
259/1.205 ~= 214.9mhz.

If you're not pushing the FSB any higher, I would try and see if you can get the memory running on the 166. It's only 15mhz above PC3200 so it shouldn't be too much of a problem ;)

Jon

Edit: ghgh got there before me :D Good advice from him though ;)
 
A couple of things:

Try pasting something into Paint to see if your memory really is stable at 1T. You might well be able to use another graphics package to test it, but Paint is commonplace and works well for this test. Many apparently stable 1T setups fail when trying to paste into Paint.

To add some explanatory numbers to ghgh's post:

"166MHz" is a wrongly labelled 5/6ths divider. With the HTT set to 260MHz, a 5/6ths memory divider would set the memory to 216.67MHz.

The usual next step down is a 2/3rds divider, probably wrongly labelled as "133MHz". 260*2/3 = 177.33.

So it looks like your memory is on a 2/3rds divider.

Your memory might work at 216.67MHz, but you would probably have to drop to 2T and perhaps relax some timings as well.

What you really need is a divider between 2/3 and 5/6, something that would give you a memory speed of around 200MHz with a 260MHz HTT. There is a program that will allow you to try to set memory dividers not available in your BIOS, but my memory of it isn't clear. A64 Tweaker, I think. I remember than when I tried a 3/4 ("150MHz") divider, my PC crashed.

It might pay off to try various combinations. For example: benchmark now, then try a 5/6 divider, to see if your memory will run at 216.67MHz at slacker settings than you are currently using, then bench to see if the higher speed and slacker timings makes things better or worse, then try a lower HTT (say, 250) with you memory at a 5/6 divider, to get the memory speed down to ~208MHz, maybe with better settings, bench again.

You can fiddle for days with this sort of thing.

EDIT: Got distracted before posting a reply, but I get the bronze medal behing ghgh and GeForce, or something :)
 
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Angilion said:
Try pasting something into Paint to see if your memory really is stable at 1T. You might well be able to use another graphics package to test it, but Paint is commonplace and works well for this test. Many apparently stable 1T setups fail when trying to paste into Paint.
Click to expand...

Wow. I never knew that. Learn something new every day :) :D
 
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