I am running a very similar configuration as you (see below). My temps running Prime 95 for 12 hours end up maxing out at 74c in a room temp of 72f on the hottest core. I'm using Shin Etsu Thermal Compund, & my D14 is blowing to the rear of my case. I'm running at 4GHz (19x210) and CPU bios setting of 1.2v. CPU-Z shows my voltage jumping from 1.2v at idle to 1.232v under load with Prime 95 though, don't know why. QPI is 1.35v and CPU PLL is 1.51050v. All else is set to defaults. My idle temps are 40-42c.
I would suggest you clean up the surfaces of your CPU and heatsink using
http://www.newegg.com/Product/Product.aspx?Item=N82E16835100010 because you have applied and removed TIM on those surfaces multiple times. Air bubbles, dust and other stuff tends to coat the surfaces making heat transfer not as good, and also, NEVER use the 'thin coat' method for spreading your TIM. A pea size amount is TOO MUCH in my opinion. I use half that. You will be surprised how much crap you take off with this cleaning kit even though it may not look dirty.
Now another note to mention, the i7-930 is a hotter running chip. It runs hotter than the 920 at the same voltage. But if you are hitting 88c with the Noctua D14 cooler at 1.22v, that is still too hot. I can hit 88c with my setup but that's with a voltage increase up to 1.375v which is the absolute maximum for that chip. The fans that come with the D14 cooler are very nice especially for being quite... but they could definitely run faster for more airflow. If you have any spare fans of the same size laying around with much higher RPMs give them a try. I have a delta 3500 RPM fan I put on for kicks and giggles and it dropped my temps by 11 degrees! Noisy though.
One more tip. Make sure when you attach or remove your cooler, you do it evenly. Screw one screw 2 turns, then the other 3 turns, then back to the first 2 turns and alternate with 2 turns from there after until they are tightened and the screws wont turn any more. This helps spread the TIM evenly and is also safer for your CPU.
Try another TIM, the batch you got with your cooler could be bad or just plain old. AS5 or Shin Etsu that I'm using now and proven TIMs.
Chassis: Cooler Master HAF-X Full Tower
CPU: Intel Core i7-930 2.88GHz 4 Core
CPU Cooler: Noctua NH-D14
Motherboard: Asus Rampage III Extreme
Power Supply: Corsair 1000HX 1000W 80 PLUS Certified Modular
Memory: Mushkin Enhanced Redline 6GB (3 x 2GB) DDR3 1600 Model 998805 (6-8-6-24 & 1T)
GPU: ZOTAC GTX 480 AMP! Edition ZT-40102-10P 1536MB 384-bit GDDR5
OS: Microsoft Windows 7 Home Premium 64-bit
Hard Drive 1: Crucial RealSSD C300 6Gbps SATA SSD 256GB (Boot, OS & Main Application Drive)
Hard Drive 2: Seagate Momentus XT 500GB Solid State Hybrid Drive 7200 RPM (RAID 0) (Game and Programs Drive)
Hard Drive 3: Seagate Momentus XT 500GB Solid State Hybrid Drive 7200 RPM (RAID 0) (Game and Programs Drive)
Hard Drive 4: Samsung EcoGreen F2 HD103SI 1TB 5400 RPM Hard Drive (Media & Storage Drive) ($55 shipped on 6/02/10)!
DVD Burner: LITE-ON Black 24X DVD+R Writer + LightScribe
Keyboard: Logitech G15 Gaming Keyboard
Headset: Creative Labs World of Warcraft Wireless Headset
Display: Samsung Syncmaster P2770H 27" Widescreen 2ms Mini-HDMI to HDMI connection
Mouse: Logitech G5 Gaming Laser Mouse
Software: Microsoft Office 2010 Professional Plus
Battery Backup: Cyber Power Smart App Sinewave PP1500SWT2 1500VA / 1000Watts Pure Sinewave, Full AVR buck/boost