Peltier unit between GPU and heatsink? - Page 1
Forum section: electronics / projects

author: drummerdimitri
author_rank: Frequent Contributor
timestamp: May 15, 2017, 08:55:58 am
content: I have an old Nvidia 8800 GTS 512 MB graphics card that is overheating unless I turn the fan speed all the way up and freezes the computer up in case I don't.I have a 72W Peltier unit I'd like to sandwich in between the GPU die and the Heatsink but given the card's 130W TDP would it help reduce the temperatures a bit or will it make things worse in therms of temperature (Pun intended)?Worst case scenario I would just buy a closed loop liquid cooler for a CPU and use it on the GPU instead and call it a day with a fan blowing on the ram and VRMs.

author: RGB255_0_0
author_rank: Frequent Contributor
timestamp: May 15, 2017, 09:06:23 am
content: Pointless. You'll soon need to cool 140W as well as the difference between your 72W Peltier and 130W from the GPU.8800GTS is 9 years(?) old or so. I'm sure there is a more elegant, more efficient GPU for your needs.And before I forget, condensation issues.

author: jeroen79
author_rank: Frequent Contributor
timestamp: May 15, 2017, 09:12:51 am
content: If it is the fan's noise that is bothering you then making it blow away even more heat is counterproductive.Find a different (larger) heatsink that requires less airflow to move the same amount of heat and a matching low rpm fan.

author: ovnr
author_rank: Frequent Contributor
timestamp: May 15, 2017, 09:17:47 am
content: Buy a new card. Seriously. The peltier will make it worse, and putting on better cooling is a massive waste of time and money.Pretty much anything on the marker is going to be better, but a low midrange example like the Geforce GTX 1050 is 6 times faster while consuming a fraction of the power, and being substantially quieter.

author: Ian.M
author_rank: Super Contributor
timestamp: May 15, 2017, 09:21:29 am
content: That idea for a mod will cook the GPU and the Pelter TEC element.I wouldn't worry about condensation - a 72W TEC cant pump 130W of heat and its extra thermal resistance + the power it uses while attempting to do so will significantly increase temperatures both sides of it.Seehttp://www.heatsink-guide.com/peltier.htmA teardown, thorough cleaning of the fan blades and heatsink fins + reassembly with a MINIMAL thickness of good quality thermal paste should restore original cooling performance unless the fan is knackered. If that doesn't restore stability, chances are its got bad caps, or the GPU has failed BGA balls or is otherwise dying.

author: drummerdimitri
author_rank: Frequent Contributor
timestamp: May 15, 2017, 09:25:07 am
content: Thanks for the replies, good to know the peltier is not going to do anything.Regarding buying a new card, I wont as I am just having fun trying to cool this card with lower noise levels as I have a beastly 2k+ $ gaming machine I built this year.I will try strapping on some CPU coolers I got laying around. If the heatsink is rated at 100 W, what will that mean for my temps if the card is consuming 130W?Also, my guess is that the heatsink rating is for pure heat power dissipation so that means the card is obviously not generating 130W of heat since some of that is actually being used to crunch graphics.

author: jeroen79
author_rank: Frequent Contributor
timestamp: May 15, 2017, 09:36:53 am
content: The heatsink's rating means it will transfer x Watts at y temperature difference.So if a heatsink can transfer 100 Watts at 30 degrees above ambient then putting 130 Watts into it would make it hotter.