I don't know what kind of threads you're running in prime95 to only get 60% utilization, but if that is it, don't even use those. 88 degrees is too hot, back down and aim for the low 80s. I always use hardware monitor, but if your temps are consistent, trust them.
On because hyperthreading is a nice application to have because it can increase performance and multitasking by 15%, so unless you can get a 15% or greater overclock by disabling it, it is nice to keep it on. (It's also nice to have for folding@home or boinc apps)
Temps Idle: Mobo=46 CPU=35 CPU0=44 CPU1=44 CPU2=41 CPU3=41
Temps Load: Mobo=46 CPU=78 CPU0=88 CPU1=88 CPU2=85 CPU3=85
3. New fans + reapply thermal paste : avg -2.5c idle -7.0c load
-Rear: TRUE120 oem fan 1600RPM 63.7CFM
-Push: S-Flex 1600RPM 63.7CFM
-Pull: S-Flex 1600RPM 63.7CFM
->Could the TRUE120 actually be using the S-Flex 1600 as its oem fan ?
-Re-apply thermal paste with single pea-size dot instead of previous (oversized) + shape
Temps Idle: Mobo=48 CPU=36 CPU0=41 CPU1=41 CPU2=39 CPU3=39
Temps Load: Mobo=48 CPU=75 CPU0=82 CPU1=80 CPU2=78 CPU3=77
4. Turn off Hyper Threading: avg -0.5c idle -10.75c load
Temps Idle: Mobo=47 CPU=38 CPU0=41 CPU1=39 CPU2=42 CPU3=36
Temps Load: Mobo=47 CPU=65 CPU0=71 CPU1=69 CPU2=68 CPU3=65
5. Lower vCore from 1.30 to 1.275 : avg -1.25c idle -3.4c load
Temps Idle: Mobo=43 CPU=38 CPU0=40 CPU1=38 CPU2=40 CPU3=35
Temps Load: Mobo=45 CPU=64 CPU0=67 CPU1=64 CPU2=64 CPU3=61
Again, in brief:
- 7.0c with new fans push/pull & better thermal paste application
- 10.75c with HyperThreading OFF
- 3.4c with lower vCore
- 22.5c total
It's true that turning HT off significantly drops temps. However, depending on what kind of applications you'll be running, it might be better to drop your OC just a hair and leave HT on. If you'll be doing rendering, video encoding, or similar highly threaded, processor limited applications, you'd be best off leaving HT on.