Or should I use this instead (http://www.newegg.ca/Product/Product.aspx?Item=N82E16835100007&_ga=1.3434672.1622490209.1427400060). Does it matter?
Thanks.
From my experience the stock thermal paste on these types of coolers are average quality. You may lose about 4C from switching it out. But if you don`t want to buy thermal paste the one included does its job quite well.
The arctic silver 5 is okay but it takes time to set to get its full cooling potential and its conductive, actric MX-4 or Noctua NT-H1 would be better. And to be honest it doesn't matter that much were talking maybe 1-3 degrees between them and the higher end stuff will probably not dry out as fast.
If you are or want to be an extreme overclocker, go for the best thermal paste you can get. If you just want you PC to run, use the supplied one and replace it with something better the next time you remove the heatsink.