Choosing Power Supply Wattage

[theolah12]

Here is my current build:
Asus M5A97
AMD Phenom II X6 1090T Processor
Western Digital Caviar Black 500 GB SATA III
Liteon iHAS324 24X DVD-RW SATA Optical Disk Drive
XFX HD-687A-ZHFC Radeon HD 6870 1GB
Antec Three Hundred Gaming Case
Thermaltake TR2 W0388RU 600W Power Supply
2x-CORSAIR XMS 4GB DDR3 SDRAM DDR3 1333

I currently just purchased a Cooler master HAF X case. One thing I was looking at upgrading while i had everything out was the power supply. I was looking at the Corsair TX2 850M Power supply. It is currently $124.16.
I know 850 is overkill for my build but I could get the TX2 750M for $107.60.

Is it worth it to just spend the extra money on a PSU that will last or just get the 750?
Since its modular for the future say when a new interface comes out such as something different than SATA, is it more than likely possible that I could just buy new cables instead of buying a whole new PSU?

I may be over thinkning this too much but just figured I would get someones opinion before buying one.
Thanks!

 

[Rugger]

The TR2 is a decent quality PSU and more than enough for your current PC. If it is providing sufficient power for your rig, then there isn't a great reason to upgrade the PSU.

A system with a single HD6870 requires a 500W PSU with at least 28A on the 12V rail and two 75W 6-pin PCIe power connectors. A system with two HD6870s running in two-way SLI requires a 600W PSU with at least 40A on the 12V rails and four 75W 6-pin PCIe power conenctors. The TT TR2 600W PSU that you have is rated for 48A on the 12V rails and is electrically sufficient for running two 6870s in SLI; it would require one molex-PCIe adapter to provide enough connectors. Bottom line is that you don't need to upgrade. If you just want to drop some more money on your PC, then there are better ways to spend that money.

 

[theolah12]

I know it's fine for my current build but i was trying more to plan for any future upgrades. I do plan on eventually putting another 6870 in there in a couple months. But as for new CPU and motherboard I will also be doing in the future. That's why I was trying to get something that was going to suit me better for future as well.

 

[Rugger]

If you're just going to SLI the 6870 and do the other upgrades you listed, then you're PSU is sufficient; nothing you've listed or discussed makes me think you need something more than your current PSU. It may not be a top tier PSU, but it is ok. The new CPU and mobo aren't going to eat significantly more power than your 1090T and current mobo. As far as futue proofing, the next gen GPUs (i.e. 7000 series AMDs and 600 series Nvidia GPUs) are less power hungry than the previous gen and the power draw on modern CPUs is also decreasing instead of increasing.