Looking for suitable replacement PSU

[film2240]

Hi,
I'm looking for a replacement PSU as my current one,even though it still works is no longer enough for my PC anymore since the GPU upgrade to a Radeon HD6950 last July.The old GPU was a Radeon HD4670 OC'd to the max and PSU still fine.

I have a core i7 920 CPU OC'd to 3GHZ when loaded (with aftermarket air cooler as its much better than stock.Stock cooler made CPU crash at above 2.8GHZ)

I need a reliable,solid PSu that can sustain the following:
1.Heavily OC'd CPU
2.Heavily OC'd Radeon HD6950 with unlocked shaders and small overvolt
3.Allows me to add my old GPU back to use as a 2 GPU PC for harder jobs (which is also heavily OC'd)
4.80GB SSD (0.15W)
5.3W 2TB eco HDD
6.DVD writer (hardly used) (20W max)
Budget is up to £130

Are the Antec HCG 900W PSUs any good (£99) for this type of load?

[D1DM]

What is the make and model of your curernt PSU?

6950s have a TDP of 200W and 4670s 70W.

Assuming that unlocked and overclocked 6950s consume as much as 6970s:

Due to my post count I can't post links to the reviews I was intending to link, so I will describe them instead.

Anandtech's recent (22/12/2011) 7970 3GB review
Shows a system with an OC'd i7-920 and 6970 using 370W under Metro2033.

Techspot's 6970 2GB (15/12/2010) review
Shows a system with an OC'd i7-920 and 6970 using 375W under Furmark.

Legitreview's 7970 3GB (21/12/2011) review
Shows a system with an OC'd i7-3960X and 6970 using 363W under Furmark.

I believe all of those numbers were taken at the wall, so you can take 10-20% off those numbers to get an idea of what those systems actually drew.

So you should add ~70W to those numbers (I work it out as 397-408W) to get an idea of what your worst case maximum power consumption is likely to be when the 4670 is installed also. So you wouldn't even be overloading a good 500W PSU. But you have to decide how much overhead you want. Personally I think 650W would be the best choice as even on maximum load you should still be (depending on the unit) within that unit's efficiency sweet spot/range.

You can get good modular 650W units for roughly half of your budget:
XFX 650W XXX Edition 80Plus Bronze Modular £70

Antec TruePower New TPN-650 80Plus Bronze Modular £65

Or a high efficiency unit:
Seasonic X-660 80Plus Gold Modular £115

Prices from Scan.

The Antec High Current Gamer 900 is a perfectly good unit and easily able to power your prospective build, but is frankly overkill for the plans you have listed atm. I'd prefer to get either a modular unit or a more efficient and quiet unit with lower wattage.