How much have you spent trying to fix it? "Upgrade" or as you say what was the cost of all the "attempts to get stable operation"?
off the top of my head
copper pipe 1"diameter 2"length, less than a buck at Lowes I think, that was cut lengthwise, flattened, cut, nibbled and shape'd to have pads down on the CP2102 and ASIC then soldered to standoffs.
standoffs from Radio Shack, maybe a buck and a half
screws from Lowes to hold the new heatsink less than a buck per package at Lowes
small fan from a triple fan insert that would snap into a drive slot to exhaust heat, free from scrap
wall wart to drive fan free from scrap (actually fan is 12v so I'm using a 10watt step-up switching converter I bought years ago for under $10 between a lower voltage wall wart and the fan)
crystal from digikey, a buck or two plus shipping from Digikey
capacitors for crystal start up network free from scrap motherboard
replacement CP2102 as the original had a deep burn spot after mistakenly plugging a strong 12v wall wart supply into a new D-Link HUD7 hub, a buck or two from Digikey plus shipping (in the interim while the BE was down I used the D-Link on my main machine and was so impressed with the improved communication between my main machine and other gear, I'm likely leaving it there)
10uf tantalum capacitor across the USB Vbus (after reading USB3.0 and USB2.0 control chip datasheets, these are needed and perhaps the non-approved early USB2.0 CyberPower hub didn't have these on outputs) a buck or two from Radio Shack
Wish I had changed the CP2102 first off. The BE has been running well for almost 3 days now on the CyberPower hub and Raspberry Pi.
soy
I have a hot air desoldering station tweaked for the extra heat which I used to remove the CP2102 but you can't count that in the cost as I bought it anticipating I may have to change some FETs on a Jalapeno I may one day finally get after their pisspoor slow production. I also bought a nice L/C meter for measuring components when I built a switching converter to bring a good sized Zenith laptop switching supply voltage down to 12v for my zTex 1.15x and used that meter to vet capacitors for the crystal start-up network.
I should note changing the CP2102 is a very delicate operation and I venture to say of those amateurs who attempt the change more than not will lose the BE completely.
) 
Ah well, moot. I devised a heatsink and fan. Moot because I changed the crystal, then added a startup network to the crystal, then added a tantalum capacitor to the USB power in. The close proximity fan caused dust to build up in lees and that degraded performance after a while. The startup network worked well, the B.E. was running on a not-approved Cyber Power hub as the room climbed into the mid-80°'s F. Usually the B.E. would shut down if the ambient got to 79°+ registering impossibly high hash rates on the minepeon cgminer. I decided to buy the D-Link DUB-H7. It arrived today. I also had purchased a Seagate Plus Backup for my main system which I'm going to use today. Both were open. The wall warts have identical plugs tho the Seagate Plus is 12v while the D-Link DUB-H7 is 5v. I noted to friends that the cheap 7 port hubs on ebay, external 5v plug same as the D-Link, hardwired to the upstream port and that 12v wall wart plugs fit perfectly (bought a L-C meter that came with one). Don't know if the D-Link upstream port is hard wired to the voltage in plug but it certainly goes to the downstream port. That gremlin that danced around on the wing of an aircraft on Twilight Zone must have guided my hand as I fired up the block erupter on the D-Link hub using the 12v wall wart. The CP2102 quickly fried. My B.E. is dead. 
