I have a e2180, gigabyte P35 dsl, ddr800 crucial balistic.  It's runs @ 3.0 ghz oc and orthos for hour 1.4 volts.  If i push it up to 3.2 it still runs fine but doesn't pass orthos.  CPU is at 1.42 volts.  Temps usually get around 69 at load.  
 
Also speed fan and Hardware monitor show my volts at 1.36 (when at 1.4 bios) and 1.38 when at 1.42 in bios.  I have an Antec 500 watt smartpower.  
 
I'm a newbie in overclocking.
 
What coolers do you suggest.
 
I don't want to go much over 50$.
 
 
 
 

http://www.newegg.com/Product/Prod [...] 6835186134

I've used a handful of those in the last year or so and have no complaints.

Best bang for buck is the AF7 referenced above.  I have one on my E2160, and it works great.  
 
What you're referring to is called v-drop (or v-droop when under load, I think).  It's normal!!   It's something that happens with Intel processors/boards when they go under load.  There are things you can do to reduce or eliminate it, but I've never done any of those.  If it's not stable under load, I just raise the V-core, and keep a closer eye on my temps.  
 
Out of curiosity, how are you getting to 3.0 and 3.2 gHz?  I'm at 2.67 gHz with my E2160, but do so at 333x8 (yes, I lowered my multiplier).  I had it at 333x9 (3.0 Ghz), but with a fairly warm apartment, and summer coming up, I lowered it, and 2.67 is still plenty fast for me personally.  If you're keeping your 2180 at it's default of 10x, then you're just raising your fsb to 300 and 320 to get to 3.0 and 3.2, right?  Depending on the rest of your set-up, it MIGHT be better to lower your multiplier to 9 or even 8 and then run your system with a higher FSB (333-375 range).  This will allow your memory to run a bit faster (depending on the divider you use), and the increased fsb should make for a bit "snappier" system.  

 
+1
 
I am getting 3.2 on my e2180 with the AC Freezer cooler.   With a 68 degree ambient temp., I am getting about 26-28 degrees idle, and mid 50s max.
 
Of course like every computer component, I spend some time thinking "what if" and "should I have gotten this instead".  Especially when seeing the latest new review of something.   But the AC is solid, and it is hard to justify spending more if within a budget system.  Especially since it is on sale at the 'egg.
 
The ONLY things I may do at some point, are replace the stock thermal compound with Arctic Silver 5, or change the orientation so that the fan blows from down to up.
 
Good luck!

...PS, I am using 8 x 400 MHz, and keeping my RAM at a 1:1 ratio.

I'd go with the Xigmatek HDT S1283, or rather, the Xigmatek HDT SD964 which appears to be much better than the AC7 for around the same price.

I went ahead and bought a AC7 yesterday and it already out for deliver today.  Neweggs fast.
 
I did look at those Xigmatec coolers and they did appear to do a nice job.  I didn't see enough reveiws to help me make a decision.  I may have made a mistake but, not the first time.  Xigmatec rifle 120mm for 36 dollars and free shipping.  Sounds nice
 
I had to drop my e2180 back to 3.1 from 3.2 ghz.  I think its from overheating.  i was playing Oblivion and my pc desided to shut off after 15 minutes of game.  It runs fine at 3.1 ghz maybe the AC7 will allow me to have a stable 3.2 or more.