View Full Version : Gettin lousy 32M times? Here's the answer!

10-24-2005, 09:50 AM
Since large SuperPi calculations like 16M and 32M are gaining populairity in fifth gear lately i see a lot of people around struggling to get some decent numbers.

Most often 1M, 2M and 4M will be fine but anything north of these values simply suck.

The solution to this is quite simple really, here's a foolproof how to:

1)Go to "start" , "run", and typ "regedit".
2)You 'll now hit windows register, click the key "Hkeylocalmachine"
3)Now click the following keys: "system" > "current control list" > "control" > "session manager" > "memory management" .
4)Here you'll find " LargeSystemCache" , click that one.
5)Now you can change the decimal value from "0" to "1".
6)Fold back all register keys and reboot machine.
7)Go to the fridge and get a beer or whatever is taking your fancy.
8)Run SuperPi 32M
9)Sit back and relax, enjoy your beer while watching SuperPi looping away at times you couldn't even imagine before this tweak.
10)Get back to the fridge to get Zeus a beer. :D

This tweak worked for me for Windows XP professional with SP2 and also for Windows 2K SP2 and SP4.


edit: Here's one from "the SuperPi factory" i just did on a new install with this tweak:


10-24-2005, 09:54 AM
How big of a gain did you see using this tweak?

10-24-2005, 09:56 AM
oooo much thanks

*gives zeus beer*

10-24-2005, 10:06 AM
How big of a gain did you see using this tweak?

Minutes, honestly minutes. ;)

10-24-2005, 12:19 PM
well with the rig below i did the regedit mod and my time did not change....HMMM
question..What does this change do to overall system performance as far as memory is concerned? Between a 0 and a 1, what is the difference, really?
Obviously it doesn't affect my SPI 32M times...

Another thing I noticed is if you goto My Computer properties, then Advanced tab, then performance settings, then advanced tab and change the memory usage to system cache it does the same thing as the regedit mod.
set to programs=0, set to system cache=1.
That's easier than going all the way through the registry anyway....

10-24-2005, 12:24 PM
I remember doing the 0 to 1 with 2k a long time ago and it did make a difference. As for XP, I'm not sure, I've never done it .

10-24-2005, 12:24 PM
heres my best at sub 3000mhz with 32m super pi
That's not even mildly funny, MM... :slap: :rolleyes:

full screenshot here (http://jason57.iwarp.com/fx57/newfolder/32mmmm.JPG)

Stay away from this thread If you choose to post like that, please...

10-24-2005, 01:07 PM
Same time as me, i had 27Mhz on the CPU less and trcd@4 :D

Just got a new Personal best 32M:


Tweak seems to work wonders. :cool:

10-24-2005, 01:12 PM
Keep in mind that:
Windows XP defaults to LargeSystemCache=0
Windows Server already has LargeSystemCache set to 1

It seems that with that tweak you're actually getting into "standard" times now... On a clean install Windows XP, changing LargeSystemCache to 1 does not make such a huge difference... It shaves off just few secs only on 32M run ;) It's still good for 32M racing, though...

10-24-2005, 01:21 PM
Well, don't know tbh, i experienced some awfull times with my old Win XP install, which was without SP2.

Then i tried Win 2K, same thing, enabled large system cache and it did very well.

Got back to XP Pro again, this time a version with SP2 and got awfull times again.

Did the tweak and was back to good numbers again.

So tbh, i don't know what determines the 0 or 1 value but i know i gained more than just a few seconds.

Here's 32M on my old XP pro install, most likely with Latge System Cache disabled:


That's almost 5 minutes too slow. :(

10-24-2005, 01:28 PM
well i gained 3 secs

10-24-2005, 01:49 PM
Try it in Win2k, and that's where you get a big gain. XP and 2k3 don't lose much since they start out all right. Win2k starts out like crap, but with the tweak on often surpasses 2k3/XP, at least it did for my 754.

10-24-2005, 02:41 PM
well do spi times matter when it comes to performance? win2k vs xp? hmm.. is it just for lower spi times or is it just faster overall?

10-24-2005, 03:50 PM
The better your computer performs, the more calculations you can do in a given amount of time. Better performance is good, for everything.