OC, Cooling, Air flow tips please

Roverno

Roverno

Roverno

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West Sussex
Hi all,

Introduction
I have been into all this computer hardware malarkey for about 8 months now and I have had my own pc built for a couple of weeks. I have a fairly small amount of experience with overclocking but I have done it to 2 or 3 PCs now. My problem is, whenever I check the temps, I know roughly what’s good an what’s bad and where my voltages should lie, roughly, but in the near future I would like to do an extreme OC on my PC so I need to get a much better idea of exactly what’s what. That makes me sound pretty stupid, oh well.
As I started writing this it was getting pretty long, so I really appreciate anybody who takes the time to read it all and maybe it will end up with some information others can use too.

Sorry in advance for the slightly questionable formatting, im not quite up to scratch on good layouts yet.

I want to go through my general hardware, RAM, current temps, voltages, air flow and cooler.

Hardware
So, the hardware reference list looks like this:

Corsair 600T White
2500k @4.6GHz- BCLK 99.8, x46 multiplier
CoolIt Vantage ALC all in one Watercooling
ASRock Extreme4 Gen3 Mobo
2x4GB Kingston HyperX Grey 1600Mhz
256GB Kingston V100 SSD
Sapphire HD 6970 2GB
OCZ Z-Series 850W
2x WD Black 1TB in Raid 1
LG Bluray- pretty irrelevant

(Tell me if I might have missed something, last time I made a list I missed the CPU out :D)

RAM
Ok so the ram I have here runs at 1.65v, which nowadays is a pretty high voltage I have heard. It is not big issue on my current OC, but will it impede on me as I got high/extreme. Should I invest in a 1.5v kit, will it really make significant difference? I will skip temps and volts for now.

Cooler
My cooler is the CoolIT Vantage ALC and as far as I can currently tell, it is fairly good. My worry is that I am probably wrong as I hear of very few other people running the same cooler. The fan seems very fast, but with a huge dead space in the middle due to a hefty motor, this gives a generally low quality feel. I have thought of buying other fans but I can’t imagine that they will give anything like the same air flow as the standard one truly moves some serious air. Opinions or experience on the cooler would be great. Comparisons/ benchmarks compared to the H80/H100 would also be great as I may switch to one of these in the future, over Christmas perhaps.

Air Flow
So below is a picture of my case inside with a fancy diagram of how my air is flowing. According to the temperature tests I did, it is a really bad flow as increasing the case fans gives higher temps. The airflow issue I have is that since the top and front fans are the same, and the mass flow rate of air must be approximately constant, there is no remaining air for the GPU or CPU to use if they are both blowing out of the case. I have tried the CPU blowing outwards, but then it seems to just take the hot GPU air and this would hinder performance. Currently it blows inwards in an attempt to take the cold exterior air and blow it over the fins, but the rising GPU air on the exterior also gets sucked in. Would it be best to change the top fan for some 120mm apache’s or something to unbalance the air flow and leave some for the GPU to pull out the back of the case?

Opinions on my case aesthetic look are also welcome. (Might take the serial number stickers etc. off my GPU, good idea?)
pcairflow.jpg

By roverno at 2011-11-19

Temps and Voltages
So the ultimate goal for me is to fast, beautiful, cold, and long lasting PC. My OC is stable at the moment and the results for temps at idle and load are below.

The low fans setting achieved by setting the dial on the front of the 600T case. Low= min, high=max.

For one test I took my side panel off and turned the fans to minimum just to see what effect it might have.

tempsresult.png

By roverno at 2011-11-19

To give you an idea of voltages I have two more pictures for you

idlelow.png

By roverno at 2011-11-19



Are my voltages reasonably high for this OC, or quite low. I wasn’t really sure as I was doing the OC, I just aimed for 4.6 and stopped when I got there. I don’t know if it is hard to tell at this level of OC, but have I done well in the silicon lottery or not? I haven’t really tried near 5GHz because I don’t think my cooler will handle it.
I also need to learn a huge amount more about motherboard UEFI/BIOS settings but these don’t seem to sink into my head very well. If anybody has links to great advice on these then I would much appreciate it.


If I get any great tips and good feedback I will make sure to publish in the reserved second post for everybody to see.

Thanks to anybody and everybody who has read everything to this point, and I greatly appreciate any opinions, links, data, benchmarks, comments you wish to leave.
 
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1. Pic size is too large
2. Temps and Voltages table is wrong (Load, high and low are back to front)
3. I'd say your vcore is slightly high. (I use 1.312-1.32v for 4.6GHz)
4. try using offset voltage instead of manual, so the vcore drops when idling. Will reduce temps and save power.
 
Will adjust the picture, wasnt sure what size i would need to make the text clear.

Temps table isnt wrong, its the problem that i have tried to explain. The increased air flow through the large fans causes a reduction in flow through the cooler, thus increasing temps. Weird i know, but it is what it is.

I will get the voltages down a bit when i do a load of OCing. how exactly do you set the offset voltage, i didnt really understand that layout for it on this UEFI???
 
Imo I'd say reverse the flow of your cpu radiator so air is exhausted <---- (in that direction) my reasoning for suggesting this is that you will be intaking warm air from the rad into your case as the radiator warms the air flowing over it. Doing still will improve your case airflow but you probably would see marginal differences.
 
To be honest, I see lots of people with watercool CPU cooler have the fans of rad blow from outside to inside of the case, rather than the typical exhaust heat through the back...is it because the cooling on the rad is more effective by drawing cool air directly from the outside then using the "warm" air inside the case?
 
Marine-RX179 said:
To be honest, I see lots of people with watercool CPU cooler have the fans of rad blow from outside to inside of the case, rather than the typical exhaust heat through the back...is it because the cooling on the rad is more effective by drawing cool air directly from the outside then using the "warm" air inside the case?
Click to expand...

Sort of, It's just that water is more thermally conductive than air so it can cool more efficiently. Hence only marginal differences regardless of warm air/cool air being flowed through it.
 
the water is only there to efficiently move heat away from the cpu. The water is then cooled by air. At the end of the day, everything is air cooled so it is the air flow over the rad that matters.

I think the problem is that the air from the case fans interputs the flow of the cpu. This slows down the flow over the fins, thus less cooling.

I have swapped the air flow to blow out the back, and my temps are 2-3 degress lower at 25% load. Which is normal as i have Fah running all the time. Gives me temps of around 32-34C.
 
Roverno said:
RAM
Ok so the ram I have here runs at 1.65v, which nowadays is a pretty high voltage I have heard. It is not big issue on my current OC, but will it impede on me as I got high/extreme. Should I invest in a 1.5v kit, will it really make significant difference? I will skip temps and volts for now.
Click to expand...

Your RAM should run @ 1.5V, I'm running the same speed overclock & the RAM runs fine @ 1.5v
 
Roverno said:
the water is only there to efficiently move heat away from the cpu. The water is then cooled by air. At the end of the day, everything is air cooled so it is the air flow over the rad that matters.

I think the problem is that the air from the case fans interputs the flow of the cpu. This slows down the flow over the fins, thus less cooling.

I have swapped the air flow to blow out the back, and my temps are 2-3 degress lower at 25% load. Which is normal as i have Fah running all the time. Gives me temps of around 32-34C.
Click to expand...

Yes, that is correct however you must consider other variables such as air pockets and differences in ambient temperatures within environments that must also be considered. Looking at your layout, your heatsink fan was most likely intaking warmer exhaust air from your gpu which suggests that the interior case temp was 2-3 degrees cooler than the ambient air surrounding the rear of your case.
 
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s7cn said:
Yes, that is correct however you must consider other variables such as air pockets and differences in ambient temperatures within environments that must also be considered. Looking at your layout, your heatsink fan was most likely intaking warmer exhaust air from your gpu which suggests that the interior case temp was 2-3 degrees cooler than the ambient air surrounding the rear of your case.
Click to expand...

Indeed, i think that is true. im most worried about my 90C temps on my 4 week old hd 6970...
 
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