715N File Copy/Move/Drag and Drop Stall

I have a very hard to explain problem with my PowerVault 715N, anytime I am moving/copying/Dragin and Dropin files to the NAS, it can get slow...very slow, or tell that resource no longer exists? It seems to Stall out, it will begin transfering or copying the data I want to it and will just stall at a certain percentage! I can cancel the copy and try it again and sometimes it works most it doesnt. What is up with that. Let me explain whats happening because I find it strange...but maybe someone out there has the same issue..or had with a fix. But then I can refresh the network and it is there (the NAS not necessarily the files I copied or moved). I checked the Cables, drivers, switch (which is a dell also) and I still have very very poor network performance. My Linkstation never had problems copying files to it, it might have been what I though was slow...but the 715N becomes really slow to the point were it isnt even talking back in forth to the sender (no network activity, and then I would get a not responding in my window...once the transfer would hang, or a resource no long exist message...but then I can refresh and boom there the NAS...strange) but I can remote desktop connect to it...and the 715N isnt doing anything out of the ordinary..CPU % is normal, RAM is decent...everything checks out. I would begin copying files to it and half way thru it would get super slow or seem to stall, but once again go right in the 715N via Remote Desktop Connection and the system isnt doing anything funny other than not transfering the files I want...zero network activity. This is drivng me crazy, I login to the unit...no High CPU time, all things look normal. The unit is a very lean setup. Necessary Service Packs, hot-fixes (critical updates) and a virus protection program that is recommended for this unit (Symantec Corp Ed). I cant figure it out. I am adding my RAM to it to bring it up to 512MB (once it comes in), according to the Tech that..might help...I wish there was some certainty. But strange, I just set the unit up last week, updated firmware before install...checked out great, new Maxtor 120GB 8MB 7200RPM drives, and Additional 256MB (still waiting to arrive). I reinstalled from scratch, the system is fresh. Looks to run excellent. no errors in the event viewer. I cant seem to understand why this device...which was designed to be fast over the network gets as slow as a floppy, and Im the only one using it. I even isolated it on its own switch with one pc moving files to it on that switch with no other pc on that switch. I had the d**n thing slow up...at one point I hit cancel and waiting and tried again...then the whole directory copied. It's sporadic, but does happen often. Strange...very strange. I even tried the other NIC in the NAS, then both, different switch, even a different PC to move files from to it. No different. Restarted...etc. Any Idea. Is there a File I am missing, driver, setting. I tried the updated drivers...I Didn't change anything. I havent played around the NIC settings...maybe I should but there are so many, I would know what to do. It is very strange. I hope someone else has the same goofy network issues, but figured it out.

I did some tests from my dual screen setup so I log into the 715N via RDP (Remote desktop Connection) and I watch the NAS and I also watch the file transfer/copy via the other screen... starts fine...and stalls...try it again...stalls cancel it, try again it goes...while I'm doing this I am monitoring the send/receive of both nics one on the NAS and one on the PC (Network Property windows) and they seem to stop sending and receiving from each other...sometime in the begin of a copy or toward the middle...it's all over. What the H**l?

Any Help would be great. I like this unit. I know it isn't defective for we had it at the Office, they retired it for a 725N because the 715N is now out of warranty so I got it, transferred the ownership, and sunk $400 in it with new drives and memory. I really want it to work. I contact support prior to get the drives so I would get the right ones. Once again any help would me so much appreciated, its driving me nuts.