Using 3/8 Tygon tubing on 1/2
 

I got the 1/2 instead of the 3/8 version of the Dangerden GPU block and since I didn't notice it until I startet ruting the hose, so I continued hooking it up. To get the hose around the 1/2 coupling I was needed too heated it up, aftervards I did clampt the hose.

The hose sits very thight around the 1/2 coupling, are the any possibilitys that the hose will give after and cause a leak, afterall it have been extented from 3/8 to 1/2.

Highly doubtful, I'm under the impression most people use tubing 1 size down from all their fittings since the seal is tighter. I have a few diferent sizes of tubing in my system, and some of them fit over barbs that are "1 size up." Especially with a high grade tubing like Tygon, I would not be concerned - I'm ust using cheapo vinyl at the moment.

[EDIT: Stupid #$@%$@# spacebar, I'm never using this Celeron again! Err "Dell QuietKey" eh? ye, I know why it's quiet- the keys aint movin'!]

Using 3/8" silicon tubing on 1/2" hoses. Leakfree since over three months. No tedencies to creep off the hose or bust.
Don´t know if tygon gets stiffer or crackes over time if exposed to daylight or anything else like that, but I wouldn´t worry. You will most likely replace the tubing during some upgrade before it becomes a problem. :)
regards
Mikael S.

I've had 3/8" ID Tygon over 1/2" OD barbs running with no hose clamps for over a year now. Not only does it not leak - it holds pressure.