BTX - A bad thing?

[rashly]

Indeed, BTX will help cool the graphics chips off, but other components are going to get much worse cooling. How many of you have opened up a case that is a couple of years old and saw all the dust in it?

Now the dust problem is going to be worse because it is going to sit directly on top of the heatsink/chip. At least when the cards were upside-down they didnt have incredible dust build-up on their main chips/heatsinks.

Hell, I've seen fans fail because the dust gets rolled up into a ball and stops the fan from freely spinning.

I always thought dust was the main reason for having them upside-down.

 

[Bouncing Zabaglione Bros.]

what does ATX, BTX stand for? or is it just a designation...?

I never understood all those years ago why they flipped the card over (chip/everything facing down) for PCI/AGP..... ISA has the card facing up.

It was to put the CPU near the top of the case where the PSU fan could blow air onto the CPU. Intel quickly revised this and had the PSU pull air off the CPU and out of the case instead. When ATX was designed, no one was thinking about 70 watt GPUs in the slot positions.

 

[AlNom]

ah... ok

thanks for the explanation

 

[Fox5]

what does ATX, BTX stand for? or is it just a designation...?

I never understood all those years ago why they flipped the card over (chip/everything facing down) for PCI/AGP..... ISA has the card facing up.

It was to put the CPU near the top of the case where the PSU fan could blow air onto the CPU. Intel quickly revised this and had the PSU pull air off the CPU and out of the case instead. When ATX was designed, no one was thinking about 70 watt GPUs in the slot positions.

If they were really thinking about GPUs with BTX, why not make the gpus plug in flat on the motherboard(or perhaps the whole card) and that way they can have the same exact cooling as cpus, and have monstrous heatsinks on them like normal cpus. Doesn't have to be a cpu type socket, but a sideways pci express port on the motherboard, and perhaps make it plug in on the short side instead of the long side. Or they could start making graphics cards as squares instead of rectangles.

 

[3dilettante]

Oh I suppose we could just use numbers, how much heat did slot a cpus generate, and how much heat do socket 754 cpus generate?

I found a pdf outlining the general cooling solution parameters, which do look about right.
www.smial.prima.de/download/23794.pdf

For Slot A, the thermal solution guidelines are set at a maximum power of 65W, which was probably for a .25 micron process. Overall, the wattage is down with the smaller geometries per transistor, but they've added a lot more, and leakage has gotten worse.

Now, for the max thermal power for socket A, it is at 76 Watts, though this the cap for the entire socket line. A64's have a maximum cap at 89 watts, though there are probably one or two speed grades before that hits. I think the Opteron 250s get above 80 watts.

A64's at lower speeds and with Cool and Quiet probably do dip below Socket A's maximum, but I'm pretty sure that within two years we'll be impressed at how the K9's latest generation is getting a cool 105 Watts.

If it weren't for cool and quiet, A64s would be much hotter, as they would be running at near full speed continuously, but I have doubts they can scale power savings massively beyond the clock throttling they have now, and that won't help under load.

 

[jvd]

You can already see them starting to prepare. The a64 and p4 boards have a plastic brace on both the front and the back to support the huge copper heatsinks .

 

[Fox5]

Oh I suppose we could just use numbers, how much heat did slot a cpus generate, and how much heat do socket 754 cpus generate?

I found a pdf outlining the general cooling solution parameters, which do look about right.
www.smial.prima.de/download/23794.pdf

For Slot A, the thermal solution guidelines are set at a maximum power of 65W, which was probably for a .25 micron process. Overall, the wattage is down with the smaller geometries per transistor, but they've added a lot more, and leakage has gotten worse.

Now, for the max thermal power for socket A, it is at 76 Watts, though this the cap for the entire socket line. A64's have a maximum cap at 89 watts, though there are probably one or two speed grades before that hits. I think the Opteron 250s get above 80 watts.

A64's at lower speeds and with Cool and Quiet probably do dip below Socket A's maximum, but I'm pretty sure that within two years we'll be impressed at how the K9's latest generation is getting a cool 105 Watts.

If it weren't for cool and quiet, A64s would be much hotter, as they would be running at near full speed continuously, but I have doubts they can scale power savings massively beyond the clock throttling they have now, and that won't help under load.

Umm..most desktop motherboards don't support cool and quiet. I think it's just that athlon 64 just run cooler than athlon xps. Besides, from what I've seen, there's only about a 5 or 6 degree(celsius) difference between an athlon 64 at idle and load with a good heatsink.

 

[Cryect]

what does ATX, BTX stand for? or is it just a designation...?

AT stands for Advanced Technoloy
ATX stands for Advanced TechnologyExtended
BTX stands for Balanced Technology Extended

 

[mczak]

Umm..most desktop motherboards don't support cool and quiet.

I believe you're very wrong there. When the A64 was brand new, indeed not all boards did. AFAIK all of todays desktop boards do, as it's a requirement from AMD (at least if you want your board to get on AMD's recommended list).

 

[Fox5]

My friend just bought a Chaintech Nforce3 250 based motherboard and it did not support cool n' quiet, and it's a fairly recent motherboard too.

 

[mczak]

My friend just bought a Chaintech Nforce3 250 based motherboard and it did not support cool n' quiet, and it's a fairly recent motherboard too.

You are right, still not all of the new boards support Cool 'n' Quiet. Chaintech has no board at all on AMD's recommended list, I'd guess this is the reason why...
Still, all decent A64 boards support it, there are plenty to chosse from. There's no reason to buy one which doesn't.

mczak

 

[Fox5]

Chaintech's isn't decent? Pretty much all athlon 64 motherboards are decent...

And there is plenty of reason to get a motherboard not supporting cool n' quiet...price. Most of the ones that support cool n' quiet are more expensive, and often by a large margin.

Anyhow, it doesn't change the fact that athlon 64s run fairly cool even under full load compared to other cpus. I believe cooler than desktop athlon xps, and cooler than pentium 4s.

 

[mczak]

Chaintech's isn't decent? Pretty much all athlon 64 motherboards are decent...

IMHO not supporting Cool 'n' Quiet disqualifies any A64 board from being decent...

And there is plenty of reason to get a motherboard not supporting cool n' quiet...price. Most of the ones that support cool n' quiet are more expensive, and often by a large margin.

I checked some local vendors here, and supporting cool 'n' quiet or not doesn't really seem to be connected to price. Even cheapies like the asrock K8S8X (which is the cheapest socket 754 board I could find at all) support it.

Anyhow, it doesn't change the fact that athlon 64s run fairly cool even under full load compared to other cpus. I believe cooler than desktop athlon xps, and cooler than pentium 4s.

Definitely cooler than prescotts, that's for sure... Actually, I'm wondering if they'll use a bit more power (no I don't expect double ) when run in 64bit mode.

 

[Vortigern_red]

I've got a pretty low cost gigabyte board and whilst it does not (or at least did not when I bought it) claim to support "cool and quiet" however if the driver is installed from AMD and the computer is set up as "Portable/laptop" in power settings it certainly reduces the CPU voltage and multiplier, however the fan speeds did not adjust to my liking so I control this with a fan controller, which I leave to its minimum at all times and the CPU never gets above 53C (Idles at about 38c)

I would be very dissappointed to buy an Nforce3 250 board (which I plan on doing soon, SKT939) and discover it did not support this. Surely all it needs is BIOS support for voltage and multiplier adjustments and these to be acessable from Windows?

 

[Quitch]

What is Cool 'n' Quiet? Sounds like the fan and processor speeds vary according to workload and temperature. Is that right?

 

[mczak]

What is Cool 'n' Quiet? Sounds like the fan and processor speeds vary according to workload and temperature. Is that right?

Not quite. Processor frequency (multiplier) and processor voltage change according to workload (not dependant on temperature). It's nothing new, for notebooks intel calls that speedstep and amd powernow since ages. Fan speed does not necessarily need to vary (I'm not sure though, AMD could have some requirement that it does for its recommended motherboard list), but of course any thermally controlled fan will run slower if the cpu outputs only 1/4th of its maximum power. Some boards are known to switch cpu fan off when the cpu is running at the minimum frequency/voltage (which is 1000Mhz/1.1V for CG stepping, the maximum power draw in that state is 22W) and the cpu gets cool enough.