I am running 3 HDDs in my lower chamber:

1x Seagate 7200.7 160 GB SATA 1.5
1x Seagate 7200.9 300 GB SATA 3
1x WD Raptor ADFD 74 GB SATA 1.5

My temps are so-so (high 30s to low 40s) with a Corsair HX 620 PSU and a S-Flex 800 RPM fan in the HDD chamber.

I read on the SCPR review of the P180/182 that duct taping the rear PSU vents will force the PSU to expel the heat from the HDDs and thus help cool the drives w/o a fan in the chamber.

I decided to do the mod, but also to keep my fan in because it is not making the system any louder. I even made a cardboard wall surrounding the top and sides of my HX620, to try to prevent airflow from being wasted and passing around the PSU instead of through it.

Sadly, my temps have not improved, and seem to have gotten slightly worse. The HX620 fan only runs at ~800rpm as well, so I guess for my idea to work I would need a faster (i.e. noisier) PSU fan.

So what experiences do you guys have with the duct tape mod? Have you been getting better or worse HDD temps?

P.S. I wanted to post pics but my camera is on loan

I got worse temps with the duct tape mod. I have a Corsair HX520 with a Yate Loon running at full speed in front the PSU. There's only two drives there. Without the mod, HDD temps were around 37C to 41C. With the mod, HDD temps were around 39C to 43C.

So the duct tape doesn't work for me either.

Do take into consideration that if you use an additional fan down there, taping the vent shut will create massive backpressure! This will work to defeat proper circulation that would occur with negative pressure.

And a cardboard wall surrounding the top and sides...? This will decrease the total volume of air available and act as insulation for the PSU. This won't improve circulation much if at all, will worsen the backpressure the fan faces, and if I understood correctly, it may in fact prevent the PSU from drawing the air from the front properly.

The whole point of taping the holes is to increase the PSU's negative pressure generation and block heated air from being recycled through it. It isn't meant to work with an added fan, and it shouldn't need any self-made air guides. And 40 degrees is pretty much normal for a Seagate. This isn't about cooling power: it's about silence.

Your drive temps are absolutely fine, really no need to worry. Do unblock those rear vents though, if you're using a fan, and get rid of the cardboard...

You could also check that the sliding cover is closed and forms a good seal between the forward part of the lower chamber (where the HDDs live) and the upper chamber - airflow will naturally take the path of least resistance and if it has a chance it would rather come in that way than through the front filter and past the HDDs.

I removed the middle fan and blocked the vents in my P180 with Corsair 520w. The HD temps dropped 4c in summer from 58c to 54c. Every bit helps with 40c ambients.

eek, 58c is high for hard drives. i ran a HD at around 55-60c for 3 weeks once and it died on me. dorm room's A/C went out and i had it in a scythe silentbox. not a good combination. usually its fine when the a/c works and ambient temps are around 20-22c

Luck of the draw? I've never had a HD fail on me.

P180 has 4 in the lower cage ~54c
Shuttle has 2 ~57c
Retired Tbird had 3 ~60c

So I guess the question I really should've asked is:

What setup provides better HDD cooling?

Duct tape mod with no fan in the lower chamber

or

No mod with fan in the lower chamber?

I use 2 wd hd enclosed in 2 scythe quite drive in the lower compartment.I also have a nexus fan blowing on the enclosures the temp that im getting is 41-44c.
The ambient temp around 35-37C.
My psu is a seasonic s12 500w.
I used to have also the duct tape before i installed the nexus fan in the lower compartment,my experience with it was that it increased the overall temp of the compartment and also the temp of the hd.
So i had the duct tape removed and added a nexus fan in front of the enclosures.
I also noticed that closing all the holes made the psu run hotter an experience that i got just by touching the sides of it.
Overall i think that having the airflow unobstructed will decrease the temp in the lower compartment.
This is my experience for the time being but i can surely understand the mechanism behind the duct tape mod and the pressure difference it creates.
The plan with the duct tape should work better if the fan of the psu was located on the back of it and not on the bottom(thats for the s12) as far as im concerned so that the fan would expel the air in a straight line motion.

If you're worried about HDD cooling, a dedicated fan will naturally provide more cooling, and you shouldn't block the rear vent.

If you're worried about silence and trust that your HDDs are built sturdy, you should experiment with a blocked and open vent to see with which your PSU does better.

I think we can safely neglect the "it felt warmer to the touch" argument.

Greetings Das_Saunamies.

So the point in closing these vents around psu is only from a point of view of silence and nothing more?
My set up is currently in low noise levels,levels that the fan of the psu could be heard if you are in close distance with the side leaflet of the p180 open.
I just mention the subjective increase in the temp of the side of the psu so that i will say that increase temp in the psu will produce more heat in the lower compartment so that the hd temp will also increase.
Thoughts?

The point of closing the vent is to prevent the PSU from possibly recycling the heated exhaust and to increase its negative pressure generation inside the lower compartment, improving HDD cooling when no additional fan is present.

Forcing the PSU to intake inside air only will have the desired theoretical effect, but there are more factors in play: where will the air inside come from, is heated exhaust really worse for the PSU than the heated air inside, and will the additional pressure be enough to make a difference? Results will vary from user to user no doubt.

It's a sound theory, and you should test yours to see which does better for you.

I don't understand why the results must vary from system to system.
I will agree about the factors that you mention but i will fail to accept that some systems will benefit from it and some would not.
One theory must be true and one allmost true ,which would that be?in real life

A system with four HDDs is different from a system with one: intake is more restricted and heat production is heavier.
A system with a bottom-intake PSU is different from a rear-intake one: pressure and airflow are generated differently as fan size and orientation are different.
And then there are the individual differences from different cabling, drive and PSU orientation and pressure sealing. Some may have to have the above hatch open more than others, lessening pressure generation through this fact alone.

What I meant to say was that in theory it happens exactly like is said: there will be no heated exhaust returning into the case through the rear vent that is now blocked, and there will be more negative pressure as a result of a more sealed environment -- the theorized results are true. The results of these, such as achieved cooling power and silence, vary by system because of the factors mentioned above.

Ideal:
A system with a single HDD, a PSU with a 1000+ RPM fan and a completely sealed compartment(intake and exhaust excluded) will offer sufficient performance for both HDD and PSU cooling to work. Heat is extracted and PSU fan won't have to ramp up to cool the unit. Both PSU and HDD work at cool temperatures.

Silent Sam:
A system with three HDDs, a PSU with an <800RPM fan and a partially sealed compartment will gain from the modification, but the benefit may fail to realize in concrete terms of cooling power or silence -- there is just too much heat and too little extraction. The fan may not ramp up as the PSU can take the heat, but HDD cooling won't be much better than without the modification. PSU will work at hotter temperatures than before, HDD cooling may see a change if PSU heat spreads in the compartment or negative pressure is generated better.

Worst:
A system with a full HDD rack, a passive PSU and an open compartment will suffer and most likely become unstable, gaining no benefit from the modification.

What happens with real systems between these is anybody's guess, and for the owner to find out.