Underclocking -how low can you go?

[Kumagoro]

Anyone given it a go just to see how long you can go? No need for pics. Just state the voltage, freqs and temperature. Must be able to boot into XP and be able to do a 1M super pi.

I am interested how low they can really go voltage wise and what the max speed you can run it at, set at its lowest voltage.

[Clunk]

Ill have a go at this later, but I think this board only goes down to 1.1v

[TiG]

we did have a super slow super pi competition in the past, it is amazing how many old machines people found.

TiG

[Clunk]

This is the best I can do. The bios wont let the fsb, multi or vcore go any lower.

6x1200 1.1v

[arthurleung]

Athlon 64 3000+ Winchester on DFI NF4 SLI-DR - 1.8Ghz 1.00V
Athlon 64 3000+ Venice on DFI NF4 SLI-DR - 1.8Ghz 0.96V
(When using Asus A8N-SLI Premium, motherboard capped at 1.1V)

Core2Duo T7200 - 2.0Ghz 0.987V
Pentium D 920 on Asus P5WD2 Premium - 2.8Ghz - 1.1875V (Limited by motherboard)

Above configuration all passed 24 hours Orthos

[Stigggeh]

i used to run my opteron 146 at 900mhz on 0.9ish v when i needed to download a large file overnight.

[Zak33]

tbh it's a good thing to find some of the cpu's that run so cool, cos frankly we dont all need uber processors and a passive system thats totally silent and that runs 24/7 for games and TV etc is a good thing

[chrestomanci]

64 Bit AMD CPUs can't go below 800MHz for technical reasons related to the hypertransport bus.

I currently have my linux system setup to change it's clock speed in response to load. It spends most of it's time at 800 MHz, and only flips up to max (2GHz) for short bursts of less than a seccond. Just now I turned off the speed boost so it sticks at 800 MHz, and it still runs quite nicely.

[Zak33]

64 Bit AMD CPUs can't go below 800MHz for technical reasons related to the hypertransport bus.

learn a new thing every day

[Noxvayl]

Its funny to read a thread like this when I have an old P4 that I can't overclock or underclock plus if it went any slower I wouldn't be able to handle it

[doddsy]

My old 3000 venice used to get run at 1.1v while running stock speeds (1.8Ghz).

[Steve B]

chresto, what processor is in your linux box?

[scrandman]

Opteron 146 (S939): Stock settings 2000MHz @ 1.4V.

Achieves: 0.9V @ 960MHz; 1.2V @ 2400MHz; 1.4V @ 2800MHz

[kalniel]

I think cool and quiet takes me down to 1.1v and 1000mhz.

[schmunk]

My Mobile Barton XP defaults to 600MHz, until you tweak it in BIOS (which then holds, until the mains supply goes - I really need to change the BIOS battery...)

[chrestomanci]

chresto, what processor is in your linux box?

64bit 3200+ socket 754, 1Gb cache

cat /proc/cpuinfo
processor       : 0
vendor_id       : AuthenticAMD
cpu family      : 15
model           : 4
model name      : AMD Athlon(tm) 64 Processor 3200+
stepping        : 8
cpu MHz         : 800.000
cache size      : 1024 KB
fpu             : yes
fpu_exception   : yes
cpuid level     : 1
wp              : yes
flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 syscall nx mmxext lm 3dnowext 3dnow up
bogomips        : 1608.77
TLB size        : 1024 4K pages
clflush size    : 64
cache_alignment : 64
address sizes   : 40 bits physical, 48 bits virtual
power management: ts fid vid ttp