Another HD-PVR fan mod

[gambitpvr]

I've had a HD-PVR for some time now. Due to the heat issue, I removed the top and had a small desktop fan blowing over the main board to keep it cool. A few weeks ago, I decided to mod the fan into the HD-PVR. I've seen several fan mods, including a nice one on these forums that used the onboard fan header but, I wanted to do something that could be easily undone. So, no cutting of the HD-PVR case or soldering to the motherboard.

I decided to mod an old 120mm case fan to run off USB and attach it to the top of my HD-PVR. Since I had several spare plugs on my powered USB hub, this seemed simple enough. I had a couple of different options for power but I went with USB.

First, I took an old USB cable, cut off one end and stripped the wires. The red is power and the black is ground. The green and white are data so, I just snipped them short. I then cut the connector off my fan's power cord and spliced the two cables together. Red to red, black to black and wrapped it with electrical tape.

Next, I removed the cover from my HD-PVR and separated the LED section from the frame. The silver middle secton (including the LEDs) just snapped apart from the main cover frame. The 120mm fan is just large enough to fit on the top cover frame. With a few washers, I was able to mount the fan to the frame from the bottom. This isn't a perfect fit but, it's tight enough to hold the fan in place so it doesn't fall onto the motherboard. As an additional bonus, those annoyingly bright LEDs are now gone

The fan blows down onto the main board. Since the case has very little ventilation, the air simply bounces off the board and rises back up to exit on either side of the fan.

I'll attach a few pics below. This is just version 1.0.... I already have few ideas to improve it.

1. I need a grill for the top of the fan.
2. The fan is a 12v fan but USB only supplies 5v. As a result, the fan only spins at about half speed. After 2 weeks of heavy use, this has proven to be enough to keep the HD-PVR cool and the low speed keeps the noise to a minimum. However, I may replace the fan with a 5v version, just to see the difference.
3. The fan isn't an exact fit. I think I can easily trim the screw holes on the fan to allow for enough clearance to align the fan to be perfectly square.

[SHS]

You do know they make 5v fan don't

[gambitpvr]

You do know they make 5v fan don't

I was building this mod out of spare parts I already had around the house. Since all I had were 12v fans of various sizes, I used the 12v 120mm fan.

I'll probably update the mod in a few weeks. When I do, I'll grab a 5v fan to test with, just for kicks. Most that I've seen already have a USB connector but, I'm curious to compare the speed and noise level with what I put together.

[Asmordean]

I modded my HD-PVR shortly after buying it when I noticed just how incredibly hot that the encoder chip was getting.

I cannot tell from your picture if you have a heatsink on the chip or not. I have the C2 revision which had a 40mm fan taped (yes taped) flush against the solid plastic side where there are no grill holes and a small aluminum heatsink hot glued to the plastic beside the fan. Quality engineering...

After removing the pointless fan and heatsink, I glued a low profile aluminum heatsink with thermal epoxy to the processor and created an ugly custom lid to hold an 80mm fan. The fan is powered by the 5v connector that is on the board so it only turns on when recording and spins quite slowly.

My recording time went from crashing after 1.5 hours to about 6 hours of continuous recording before crashes. This means that unless I leave it running on live TV by accident, it never crashes anymore.

I suggest two things to you:
1. If you don't have any heatsink on that chip, go epoxy one on. Even a small RAM heatsink will make a huge difference.
2. If your board has an internal 5v connector (not all of them do) then use that for a nice clean setup that only turns on when it's needed.

[thomaszoo]

Thanks for the idea. I wanted to do the mod with the internal connector so that it only ran when the HD PVR was being used, but mine does not have one. I currently have a fan connected to a small power brick that powers it. But with this I can plug it into my server and since it sleeps when not in use (>75% of the time), the fan will be off, too.

Thanks for a simple yet useful solution.

Wayne

[gambitpvr]

I applied the fan mod to my brother-in-law's HD-PVR so, I decided to clean it up a little.

This time I used a 5v fan from Cooler Guys. It came pre-wired with a USB plug. From what I can tell, it is only slightly slower than my 12v fan but, since the fan is only 3/4 inch from the main board, it's not a noticable difference.

For washers, this time I used 5/32 x 7/8 Fender Washers from the hardware store. They are a bit smaller than what I used last time but, the center hole is just large enough for the fan mounting screws to fit through. I painted them black, just for kicks. I also trimmed the washer for the back corner to avoid contact with the AV jacks instead of using a smaller washer.

On the top, I put a metal mesh grill, also from Cooler Guys. This gives it a nice finished looked.

I've attached a few pics of the updated mod.

[SHS]

Thing you need
3" Hole saw
Drill bits
5v 80mm case fan
It you don't know how to solder really well check with your local TV Repair man.
This clip show where add fan wire so that it come on when recording

This clip show where add fan wire so that it come on when recording

This where you want add holes at if your HD-PVR did come with holes all ready in bottom of the case.

Center a mark the top of case cover and per-hole a main hole for hole saw then use the 3" hole saw to finsh it then you need to drill out 4 small hole for the fan screw used a small bit that tab smaller then the fan screw hole frist then step up bit size hole so it allow the fan screw to eazy fall thought.
Note some HD-PVR come with Blue LED you can remove theme.

See all done not set the fan up to blow out the top of the case

[saulin]

Oh no. I was just looking into getting one of these. So they overheat? I know how to solder but I would not want to do these mods since they will void the warranty. Is overheating a common issue with the HD-PVR?

[SHS]

Originally Posted by saulin

Oh no. I was just looking into getting one of these. So they overheat? I know how to solder but I would not want to do these mods since they will void the warranty. Is overheating a common issue with the HD-PVR?

Yes it a common issue with long hour's of recording and yes it void your warranty if it new under warranty.
I should have point out that there are newer device board lay out that has the fan header all ready on them but no pin's solder on them see the below web page on the board layout it is labeled J307 on Rev E1 and D1 I think maybe the same as well mine is Rev C2 and do know that C1 and C2 are the same boards there the mod I post will work.
Rev D1 and E1 should have vent holes for airflow on buttom of the unit
http://forums.sagetv.com/forums/showthread.php?t=50822

[stevech]

FYI
HD-PVR I just purchased is marked Rev F1. Vent holes in bottom.


I don't have it working with Sage yet...
http://forums.sagetv.com/forums/showthread.php?t=55683

[gambitpvr]

I know how to solder but I would not want to do these mods since they will void the warranty.

My original posts ( #1 and #6 ) are 'soft' mods. They don't cut or solder anything so, you can undo them to put the HD-PVR back to it's original configuration.

I've recorded back to back recording for 6 straight hours without issue with this mod. So, overheating isn't a problem anymore for me.

[Savage1701]

FWIW, I did the following:

120mm fan on 1" rubber/nylon "standoffs" from the hardware store parts area on top and bottom of the fan to minimize the "dead space" vortex. Small, thin coat of silicon adhesive on top and bottom feet so no vibration or "walking" of the unit. Standoffs silicon adhesive'd to the fan on top and bottom of fan as well to hold them in place, of course.

Placed HD-PVR on top of 1" upper rubber washer "legs".

Fan blows 24x7x365 up into HD-PVR with no permanent mods either. Seems to keep it cool.

Fan powered from Molex PCI slot backplate on my Sage server. Get these for a few bucks on Ebay. They have female Molex and Fan adapters on them.

[BitBass]

I'll add my very simple bit of hackery:

I have a C1 model and it's been hanging up the last week or so. I figured this might be because of the outside temp so why not try some cooling. I poked around on the board and found some through holes near the barrel plug that were running at 5v I snipped a couple of single header pins and soldered (poorly) some bare wire from an 80mm 12v case fan.



I put some heatshrink on the wires and some electrical tape to hold them in place.



It turns out the space in the clear plastic is exactly the same size as the 80mm fan. I ran some zip ties around it to hang it above. It pushes air in and there's enough room to the side of the fan to exhaust it:



It's not something you'd want to be bumping around but mine just sits in a rack in the basement. It's not going anywhere. The best part is none of the changes are permanent. Very easy to return it to normal and the power draw is all self contained.

Time will tell if it makes a difference. Thanks for doing the leg work everyone!

[MattHelm]

All,
I used this fan:
http://www.newegg.com/Product/Produc...82E16835119129

Nice thing is, it comes with a little adapter that you can solder to the PCB (I just did mine from the top side) and then it's even detachable from the PCB! I'd post a pic, but it looks like crap, as I used white silicone as glue (only thing in the house.

I did mine like BitBass, using just the clear cover.