Single Rail PSU around $50

[jiggamanjb]

title says what i'm looking for. the best single rail PSU with a nice 12v line and perferabbly adjustable pots.

[nn_step]

What do you intend on running?
And as a general rule of thumb the Min Budget should be $100
Because a Bad PSU when it dies on you.. takes out Everything else in the Case with it...

[krypt0]

Yeah definitely not something you want to skimp on, especially if you plan on overclocking.

[Nouseforaname]

Just what sort of size are you looking for? If you're willing to stick to 400W, and if you're willing to go secondhand you could try getting a zalman or hiper psu on ebay (they sometimes go for the uk equivalent of $50 (£30) on ebay uk).
I'd go with what everyone says about not skimping on your psu, but depending on the spec of your system, you may be okay with a 400W, if it's good quality, and there's always a good reduction in the price of stuff which is last years model, as it were; PSUs seem to massively lose value when they're second user.
It's worth calculating how many watts you actually need, using a psu calculator (see the guides below)- it may be less than you think.
Avoid cheap, massive wattage PSUs. They're pants.
I'll stop now, but I strongly recommend you take the time to try this guide:
http://forums.extremeoverclocking.com/showthread.php?t=136602
I found it extremely helpful when upgrading (to an enermax 500W).
While searching for that, I also found this, little less comprehensive but still worth a read;
http://forums.guru3d.com/showthread.php?t=161496y.

[charlie]

The closest I can get for you is the FAMOUS Fortron FSP400-60THN-R "Blue Storm". Hella' good PSU... rated at 400w but better than most 500w models. It's dual rail, but that's ok...

$67

http://www.newegg.com/Product/Product.asp?Item=N82E16817104935

http://images10.newegg.com/NeweggImage/productimage/17-104-935-06.JPG