Personal computing discussed
Moderators: renee, Flying Fox, morphine
Duct Tape Dude wrote:Most motherboards allow you to change the max TDP of a CPU. I have my home server (Sandy Bridge Celeron, 2x2.6GHz) sitting at a 35W max TDP instead of the stock 45W. It's a bit cooler/quieter at load now. I haven't looked into hardware undervolting before, though I know it's also common. The TDP rating is the easiest to just set-and-forget though.
Flying Fox wrote:That is actually a relatively new BIOS feature that I have not seen before (my last motherboard is a P55 chipset one). Setting max TDP can be simpler. Which motherboard is in your system? Undervolt (tested of course) can maintain the same clock. The auto max TDP may involve the motherboard messing with clocks though.
Waco wrote:Perhaps, but even with limited TDP a full-fat leaky 2600K/3770K/4770K is going to use more power than the S or T variants at similar performance levels.
Waco wrote:It's the case much of time time since the K series chips tend to be leaky where the S and T chips are binned for low leakage and low voltage operation.
If I have time tonight or tomorrow I'll play on my test rig again and see what it really does when playing with the power settings.
Bauxite wrote:I'll tell you guys another secret.
People are wrong about using the stock chips and just by downclocking/undervolting them means you are automagically ok. (or that they even boot or don't crash, or that the board supports it, or that it works outside of winblows)
They can still overheat in real world use when there is no headroom, running 24/7 in higher temp industrial and/or fanless. Been there, done that, that home cpu idling away most of its lifetime doesn't prove anything.
Flying Fox wrote:That's why you need to stress test the heck out of a undervolting/underclocking set up the same as you test an overclocking/overvolting setup. It is all about finding the limit, just in the other direction.