Here is how I modified my Quadra 700 for higher speed. Previously I had been using a Variable Speed Overdrive for accelerating my CPU but this modification is testing out as more stable at higher speeds.  Your mileage may vary. The top speed you achieve cannot be predicted before hand. My personal Q700 has tested fine up to 32 mhz thus far. I didn't have higher speed clock oscillators on hand to test higher speeds.  Parts  	Clock Oscillators (4 pin TTL variety) You will need a selection of 	speeds beginning at 50 mhz on up. The CPU will run at 1/2 the 	oscillator speed. The original one is a 50 mhz unit. I recommend 	getting a 50 mhz clock in case you damage the existing one.  	   I obtained my clock oscillators from DigiKey 1-800-344-4539 for 	   less than $5.00 each. Some of their part numbers are:  		   50 mhz TTL Clock Oscillator (part # X121) 		   62 mhz TTL Clock Oscillator (part # X136) 		   66 mhz TTL Clock Oscillator (part # CTX137)  	   Don't get the half size clock oscillators. They won't fit.  	   There are also CMOS clock oscillators. I haven't tried one in a 	   Quadra. (They work fine in IIsi's) 	    	Socket: Obtain a 4 pin socket which is in the same form factor as 	   a 14 pin DIP package. Alternatively, use 4 machined socket pins 	   from an Augat style socket. Just cut them out of the socket.  	Cooling Fan: A very small 12 volt fan to keep the CPU cool is a  	   must. My VSO came with a specially modified heatsink which had 	   a fan built onto it. It had a pass-through connector which 	   tapped into the hard drive power cable. You should rig up  	   something similar or risk frying your CPU. 	    Procedure  1)  Insert usual disclaimer and antistatic warnings here.  2)  Remove the top lid of the machine. You will see the floppy disk and     hard drive mounted in a plastic tower. Follow the usual anti-static     precautions and of course make sure the machine is OFF when you do     this. Unplug ALL cables, wall and monitor power supply cords from 	the back of the mac.   3)  Remove the power supply by pulling the plastic interlocking tab on the     tower forward and simultaneously pulling the power supply straight up.     The tab is a piece of plastic from the left posterior aspect of the     tower which extends downward to hook on to the power supply. You may     also feel a horseshoe shaped piece at the right portion of the power     supply. Leave that alone. The plastic tab from the tower is all you     need release.   4)  Look at the rear of the tower assembly. You will see the flat ribbon     SCSI connector to the hard drive, a power cable and a flat ribbon cable     leading to the floppy drive. Disconnect all these from the motherboard.     The hard drive power cable connector has a tab which must be squeezed     to release it.                                              5)  Unplug the drive activity LED from its clear plastic mount  6)  Look down the posterior, cylindrical section of the plastic tower. A     phillips head screw is at the base. Remove it, taking care not to drop     it into the case. A bit of gummy glue on your screwdriver is helpful     here.  7)  Remove the tower assembly by pulling medially the plastic tab on the     right side of the tower. This tab prevents the tower from sliding 	posteriorly. Slide the entire tower assembly 1 cm posteriorly then 	lift the tower assembly straight up and out of the case.  8)  Remove the interrupt switch assembly. It is a strangely shaped plastic     device at the left, front edge of the motherboard. Pull the middle, 	rear plastic prong up and forward. The entire device will release. 	 9)  Unplug the speaker cable. Squeeze the plastic tab on the speaker to     free it then swing it backwards to free it from the case. 	 10) Remove the motherboard form the case. Lift the front right corner of     the motherboard about 1 mm. This allows it to clear the clear plastic 	Power light guide. Slide the motherboard forward about 1 cm. The 	motherboard then comes directly out. 	 11) Locate the 50 mhz clock crystal. It is a small metal box near the     CPU chip. Note and remember its orientation. The new clock oscillators 	must be aligned with pin 1 in the same orientation. 	 	Very carefully desolder and remove the old clock oscillator. Some of 	the pins may be bent over. Simply desolder then unbend them. Be sure 	your desoldering iron is hot enough before heating the board. 	 	I used a suction desoldering iron to accomplish this task. This is 	NOT appropriate for a first soldering experience. The motherboard is 	a multi-layer design with very fine traces - easily damaged without 	proper care. 	 12) Install your socket or socket pins where the old oscillator once was.  13) Put a 50 mhz clock oscillator into the new socket. You could use the 	old clock but it has solder on its pins. This may come of inside the 	socket and cause corrosion problems later. I suggest using a new 	50 mhz clock. 	 14) Install your cooling fan system to complete the modification. 	 14) Reinsert the motherboard and slide it into place.  15) Snap in the interrupt switch assembly and speaker to lock the mother     board firmly. Plug the speaker wire back into the motherboard. 	 16) Reinstall the tower assembly by first placing the right wall of the     tower against the right wall of the case with the tower assembly about 	1 cm posterior of its intended position. Lower the tower assembly into 	place while maintaining contact with the right wall of the case.     Once fully down, slide the tower assembly anteriorly until it clicks     into place. 	 17) Reconnect the motherboard ends of the cables. DONT'T FORGET THE FLOPPY     DRIVE CABLE.  18) Replace the phillips head screw  19) Drop the power supply straight down into place until it clicks in.  20) Plug the hard drive activity light back into its clear plastic mount.  21) Reattach your cables and power cords. Cross your fingers and turn      on the Mac. It should make the usual power on chord. If it doesn't, 	something is amiss. Immediately turn of the power and recheck your 	handiwork. If all is not well, you have my sincere condolences. 	 	Hopefully, all will work normally. Turn the machine back off and 	replace the 50 mhz clock oscillator with a faster one. Reboot and 	be astounded.  	 	You will need to fully test the machine for many hours before deciding 	a particular speed is truly usable. With my VSO, a machine lock-up 	might take 8 hours of operation to occur. In the brief time since 	modifying my clock oscillator (36 hours) I have not had a single 	problem. 	 Good Luck to all who attempt this modification. There is a small but real risk, but you could well reach Quadra 950 speeds or higher with less than $50 in parts.