I used to run Quad SLI (two GTX 295s) and a very heavily overclocked E4500 Core 2 (2.2 to 3.4ghz) from a 625w Enermax Modu II. Both 295s were overclocked too. TBH I would just see how it runs. Your PSU will have a safety cut out feature any way. As for SLI? it's been very good for the last two years or so. Before that I used to get issues but Nvidia have really embraced multi GPU systems and as such it's pretty slick now. If you need any bridges LMK dude. I've got about ten. I would make sure you space the cards as far apart as the motherboard allows. The main issue with SLI is always heat. As you can see from the picture above I made sure the 295s could breathe and fitted an extra fan to the side of the PC to bring in cold air.
I've had this discussion a few times on here. Glenn's system will never go near 600w from the wall, let alone what it actually uses in DC. I had a 3770k @ 4.7, 2 x EVGA 670 4GBs overclocked, water pump, case lighting, 2 SSDs 1 HDD, 16GB RAM. From the wall the highest I ever saw was 477w, including running furmark and smallfft at the same time and all the benchmarks you can think of. You PSU is fine. I would bet my rig on it
This thread has got me thinking that my 850w psu might be a tad overpowered running Intel HD Graphics
Just stick with your current PSU it'll be fine! Here's a thread where I test a small 400 Watt Enermax PSU... http://forums.bit-tech.net/showthread.php?t=228961 Components include a hot running 680i Motherboard, 4 x 1GB RAM, Hitachi HDD, E8500 (OC 4GHz), GTX 480 (undervolted but at stock clocks), D5 Vario Pump add a couple of Delta fans (power hungry little beasts!) and a small lighting system not forgetting a soundcard and it runs perfectly! In fact I have enough headroom to go SLI on the GTX 480. I did have a PhysX card using an 8800GT with no problems but have since removed it to tidy up the water cooling. Did reveal the shutdown Wattage was 600 on this Enermax PSU however, but that was only triggered due to overclocking the GTX 480!
OK guys, change of heart, will stay with my current PSU but will keep an eye on things. Thanks all. As usual useful differences of opinion. Great stuff.
That was my intention but after advice from here I decided that there is really not much around that A) I can afford and B) is really much of an upgrade and C) the second 670 will be bought via the Marketplace at a fair price.
sli seems to be fine in everything unless you wont to play battlefield 3 then just seems to crash after 5 seconds I giving up on things to try to resolve it
Get a wattometer. Stick with your current power supply. Any power requirements will show up on the power meter. It'll give you a definitive answer.
Go SLI it's great fun, especially if you've never done it before Never had a problem with sli running games. Ever. (2x460s, 2x670s, 2x680s)
I have. F1 2012 was an example. It was just broken to heck on SLI. I also had sky issues in Skyrim but the issues were fixed pretty quickly. I've always said that if you go SLI you should not do it on slow cards like the GTX 460. If you have an issue then you can't fall back on one card because the one entry level card is not good enough. So as mad as it sounds I've always personally recommended going SLI with two high end cards, that way if a game doesn't like it you can just go into the Nvidia control panel and disable SLI for that specific game. But yeah, as I say I've had few issues (though I have had some). What irks me is when Nvidia release a new driver for a specific game like BF3 yet break SLI support for older games. As an example if I run Fallout 3 on the latest drivers it flickers like a pig. It's not an issue though because of course, one GTX 670 is more than enough for Fallout 3. What I will say is that Tri SLI, Quad SLI and four way SLI (yes they are different) are to be avoided at all costs. It's hard enough getting a game dev to support two GPUs, none will bother with more. When I ran Quad SLI I only did so because I wanted to use Surround and the single PCB 295 only has two monitor outputs. So I needed the second card in there just to plug the third monitor in. It was a nightmare. A game would run smoothly until you either paused it or it stopped to load the next level. At which point it would break Quad SLI and the only way to fix this was to turn off power saving and pretty much run all four GPU cores @ 100% all of the time, full load in the control panel. All I know is my radiator was turned off until Surround annoyed me enough to break it down and give up. But SLI itself is something Nvidia take a lot of pride in (unlike AMD with Crossfire until PCPER caught them in a big lie) so you should only ever have minor issues that are quickly fixed with patches and or driver updates. It's well worth a go if you want to run titles like Crysis 3 with any sort of AA.
670's in SLI work great I'm using 4 of them and I've never had a problem with 2, 3, or 4way SLI That's my plan but 4
