I'm not sure when I bought this Scythe SY1225SL12M fan that I've got on my TRUE rev.C as it doesn't appear that comes with a fan.

Anyway, at 12v/1300RPM it's far too loud so I stuck a Zalman RC56 resistor cable on it, which brings it down to 860RPM but then it has a very annoying chirping sound which is much worse than the air noise at full speed. I've got a Zalman RC100 but I don't think it's advisable to run it much slower as I've got my Phenom II X4 955 overclocked to 3.8Ghz. At 12v, the CPU idles around 40c but I've got it on the bench, not in a case, so obviously that keeps temperatures lower and they'll rise once I get a case for it.

So I'm looking for suggestions for replacements that will work well with the TRUE and this CPU?

Why not just get the "L" version of that fan? It comes stock at 800rpm. I've had several, none have exhibited any chirping with mobo header control or a FanMate. They will go down to ~500rpms easy too.

What I was perhaps thinking (and should have mentioned in my first post) is getting a 4-pin fan, as with three pin ones (like the "M") my MSI 990FXA-GD80 board is unable to adjust the speed of the fan. So I'd like to get something that can run a bit faster when the CPU heats up and nice and slow and quiet the rest of the time.

I'm not sure exactly when I bought the "M", probably around April 2011 when I bought the TRUE. I used to run it slow a while ago with the resistor and didn't notice the chirping, so it must have developed since then.

The Scythe SY1225SL12LM-P PWM would be worth considering if you want to say with Scythe. This was the fan fitted as standard to the Mugen 2, see the SPCR Mugen 2 review for details http://www.silentpcreview.com/article961-page5.html. Current UK Scythe SY1225SL12LM-P prices can be as low as £5, from this source http://www.amazon.co.uk/Scythe-Case-74CFM-Stream-SY1225SL12LM-P/dp/B002SCPH9M/ref=pd_sxp_f_pt.

A SY1225SL12LM-P setup will give a quiet idle with fan speed automatically elevating when the system is under a gaming load. The GD80 motherboard BIOS smart fan controls should in any case allow you to balance CPU temps against fan noise.

Given your level of overclock, it might be worth considering deploying a second SY1225SL12LM-P as an exhaust fan if your case has a 120mm exhaust fitment, and linking it to the CPU as part of a PWM fan chain. This would increase overall case airflow as the CPU heated up and limit the maximum speed to which the CPU fan is likely to run. Doing this would need a PWM splitter cable. Typically these cables allow three, four or five PWM fans to be controlled by the CPU fan PWM control signal, but draw power for all the fans separately from a PSU molex or SATA power header. An example is the Akasa AK-CBFA06-30 which costs around £5 from this source http://www.scan.co.uk/products/akasa-flexa-fp3s-3x-pwm-fan-splitter-cable-with-sata-power-black-braided.

Thanks, that sounds like a good plan. I can't hold one bad fan against Scythe as I know they're normally very good, so I don't mind trying another model. That Amazon link is £9.47 once you include P&P though

Yeah, I'll be able to use the GD80 or speedfan to adjust the speed of a 4-pin fan, it just doesn't work with 3-pin fans.

I haven't built my case yet so it's just on the bench at the moment but it will have a 120mm exhaust when I build it, so it would be good to have that linked to the CPU temperature as well. Scan charge a lot of postage these days on orders under £100, so I try and buy stuff from CCLonline these days as they have free shipping. Would this be a suitable PWM splitter? http://www.cclonline.com/product/65066/ ... r/CAB1647/

I don't think they have any suitable fans unfortunately though.

Yes, a simple Y cable is fine for just two PWM fans.

Cool, thanks. I'll see if I can find the SY1225SL12LM-P anywhere cheaper as I don't really want to spend £20 on two fans.

Hmm, it's up to £11 on Amazon now.

Would this Arctic F12 PWM for £4.75 be any good instead? http://www.amazon.co.uk/Arctic-Cooling- ... omputers_5

Yes, the Arctic F12 PWM is OK and you can buy two of them for less than the cost of a Scythe. Also they have PWM sharing built in so you can chain them without additional expense.

Thanks, that's pretty cool. I'll get a couple of those then. Cheers

So I'm using a single Artic F12 on the TRUE, with the board still on the bench.

I'm finding it tricky to get it to speed up fully under load though. I had the min speed set to 12.5% and target temp 40c (the lowest setting) in the BIOS and that results in this (CPU at 3.6ghz@1.375v, although as you can see the VID stays at 1.350v whilst Vcore varies between 1.368v and 1.400v):



So the fan idles at 831RPM but only spins up to 1113RPM max at 45c (this is for the CPU socket, the Core is 10c higher at 55c).

So I then changed the min speed to 25% which gives a min 1046RPM and max 1180RPM at 43c. I would have thought with a target temp of 40c, approaching and certainly exceeding that the fan should spin up to full speed, which is 1350RPM for the F12.



Note, the temps are a bit lower here because I turned off the heating and opened the window, not to mention it had only been running Prime for 15mins compared to 45mins for the first test.

I've been advised that core temps approaching 55c are not good and I'm inclined to agree as this is not a particular high overclock from 3.2Ghz to 3.6Ghz. Perhaps it would be a bit better in a case with an exhaust fan, which would certainly cool the VRMs a bit but then again, even with the best airflow, heat tends to build up inside cases so I'm not sure it would be any better.

I can't find any notes for this system and it's never been in a case anyway but I've got some for my Phenom II X3 720 system, which is overclocked from 2.8Ghz to 3.2Ghz and cooled with a SI-128SE.



I think I was using Speedfan at the time so had to work out which sensor was which myself and it looks like I got the CPU and Core readings mixed up. Anyway, at 1.392v the CPU gets about as hot as this Phenom II X4 955 @3.6Ghz, whilst at 1.312v it's 4c cooler.

With Target Temp 40c, Minimum Speed 50%, it still doesn't spin up and at the moment under testing I've got CPU 40c, Core 50c and the fan's only at 1267RPM. Without SMART FAN it runs around 1400RPM I think, so it's frustrating it won't speed up to use it's potential to cool my CPU better and I don't want the noise of it running at full speed unnecessarily, which is why I got a PWM fan.

This Arctic F12 PWM fan really doesn't seem that effective with my TRUE.

Even at default 3.2Ghz and the fan at 1230RPM, Prime95 Blend makes the Core go to 53c and the CPU to 42c.

I can't actually feel any air coming out the other side of the TRUE. If I hold my finger near the top of the fan where it overhangs the TRUE I can feel a good blast of cold air there. Maybe it's just hard to feel the air after it's been through the TRUE and heated up but I'd think I should still feel something, so maybe it's just too weak to work effectively with the TRUE.

It just gets better with this fan, it's started squeaking at full speed now

Does anyone know of a program that will still let me set SMART FAN in the BIOS to keep it quiet most of the time but that I can run with a commandline in a batchfile before playing games to make it run at full speed? I only need this because the SMART FAN feature doesn't let the fan go to full speed (around 1470RPM) but limits it to around 1200RPM.

I know I could probably use Speedfan to limit the fan speed instead of the SMART FAN feature but I'd rather avoid needing to have another program running all the time.